Petrographic Report on 11 Polished Thin Sections€¦ · Petrographic Report on 11 Polished Thin...

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Petrographic Report on 11 Polished Thin Sections:

Orefinders Resources Inc., Mirado Gold Project,

Northeastern, Ontario.

Samples submitted by Ken Rattee,

Orefinders Resources Ltd.,

110 – 2300 Carrington Road,

West Kelowna, British Columbia.

V4T 2N6

Jim Oliver, Ph.D., P.Geo.

Kamloops, B.C.

May 8, 2014.

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TABLE OF CONTENTS

page

Overview………………………………………………………………………………. 3

Characterization of Sample Suite Protoliths………………………………………… 3

Definition of the regional metamorphic field ……………………………………….. 9

Documentation of the hydrothermal alteration assemblage ………………………… 10

Sulphide and vein paragenesis………………………………………………………... 11

Structural characteristics……………………………………………………………… 12

Interpretations – relevance to exploration data……………………………………….. 12

APPENDIX I.

PETROGRAPHIC DESCRIPTIONS.

Sample Number Page

MD 13 – 03 @ 163.7 m. ……………………………………………………………………. 15

MD 13 – 09 @ 176.1 m ……………………………………………………………………. 21

MD 13 – 13 @ 31.0 m ……………………………………………………………………… 27

MD 13 – 16 @ 85.2 m………………………………………………………………………. 31

MD 13 – 19 @ 97.4 m ……………………………………………………………………… 36

MD 13 – 21 @ 434.6 m …………………………………………………………………….. 41

MD 13 – 22 @ 49.6 m …………………………………………………………………….... 45

MD 13 – 26 @ 309.8 m ……………………………………………………………………. 49

MD 13 – 27 @ 72.35 m ……………………………………………………………………. 55

MD 13 – 29 @ 20.7 m ……………………………………………………………………... 59

MD 13 – 14 @ 318.6 m …………………………………………………………………… 64

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Overview:

From a sample suite of 11 samples submitted for polished thin section and petrographic analysis,

general introductory comments are provided with respect to:

Characterization of sample protolith.

Definition of the regional metamorphic field.

Documentation of the hydrothermal alteration assemblages.

Sulphide and vein paragenesis.

Structural characteristics.

Interpretations – relevance to exploration data.

On a sample by sample basis, the report examines the following characteristics:

Macroscale photographs of the sample after staining for potassium feldspar.

The rock protolith.

Relevant alteration assemblages.

Macroscale sample characteristics.

Microscale mineralogical and textural characteristics.

Fluorescent properties.

The magnetic susceptibility of the sample.

Relevant microscale structural details.

Representative transmitted and reflective light photomicrographs.

Responses to the client’s specific questions for some thin sections are provided.

Characterization of Sample Suite Protolith

The suite of 11 samples contains five principle lithologic units. One of these samples has been

cut from a semi-massive sulphide vein and determination of the rock protolith is not possible. On

each of the following generalized descriptions, selective photomicrographs are included. For

detailed descriptions of these rock units, refer to the appropriate sample entry in Appendix I. For

the remaining 10 samples the following protoliths are recognized:

a. Supracrustal Rock Units:

Magnesium Rich Monolithologic Intermediate Tuffs and Breccias (MD 13 – 09 @ 176.1 m)

Mg rich tuffaceous rocks are an important unit as they are commonly documented close to the

immediate structural hanging wall position to the underlying, fine grained felsic (“grey dacite”)

flows. At the macroscale, the unit is always characterized by the presence of highly elongate

dark green black fragments. At the microscale this rock unit contains abundant chloritoid. The

chemical composition of this mineral (a hydrous iron – magnesium alumina silicate) is most

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typically found in metamorphosed pelitic sediments . It also forms in mafic volcanic rocks in the

stratigraphic footwall to VMS deposits, e.g. Louvicourt and Golden Grove and is also associated

with several well-known gold deposits including Casa Berardi. Of the 11 polished thin sections,

this mineral is only identified in one section. It may be interpreted as either a regional

metamorphic mineral or a unique mineral related to hydrothermal alteration processes.

a b

Plate 1. Macroscale and microscale images, sample, MD 13 – 09 @ 176.1 . The cuspate elongate form of the

lapilli sized fragments in the off-cut blank, plate 1a, suggests that the protolith is an angular, monolithologic

breccias. The presence of abundant chloritoid crystals, plate 1b, indicates that the protolith is Fe – Mg enriched.

Mafic Lapilli Fragmentals (Sample MD 13 – 22 @ 49.6 m).

This sample which is a mafic fragmental has stark compositional and textural distinctions

relative to the previously documented chloritoid bearing rock units. The slightly pale coloration

of the rock unit is a function of elevated chlorite contents. The overall color index, absence of

free quartz and absence of potassium feldspars suggest that this rock lies in mafic, not

intermediate, fields.

a b

Plate 2. Mafic fragmentals. This sample which has been collected from a mafic volcanic unit to the north of the

Mirado shaft shows significantly enhanced strain fabrics, contains no free quartz and no chloritoid. Off cut block is

15 mm in length, plate 2a. Microstructural characteristics on plate 2b suggests the rock has been subject to apparent

dextral strain. Refer to the relevant appendix entry for complete descriptive details.

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“Amygdaloidal Intermediate Flows (MD 13 – 13 @ 31.0 m)

The origin and protolith of this unit is enigmatic. It has been cored several times in the 2013

Orefinders drilling and a “vesicular or amygdaloidal” rock unit is repeatedly documented in

archival drill records and geological reports. This rock unit commonly structurally overlies more

massive, and finer grained “grey dacite” flows.

a b

Plate 3. Amygdaloidal Flow. In hand specimen, plate 3a, this rock is characterized by mottled epidote-chlorite

aggregates which have extensively overprinted primary mafic mineral assemblages. The very fine grained and

quenched nature of the matrix, plate 3b, strongly suggests that this rock unit has an extrusive, not intrusive origin.

Detailed descriptions are contained in the relevant Appendix descriptions.

Intermediate Flows (MD 13 – 19 @ 97.4 m, MD 13 – 29 @ 20.7m; MD 13 – 14 @ 318.6 m)

These rocks form useful stratigraphic markers and are commonly noted as fine grained light

grey-cream sporadically pyritic intermediate, dacitic flows. Large quartz phenocrysts are

virtually never identified and all samples lack any evidence of flow laminations or preserved

primary compositional layers. The samples are representative of massive, coherent flow

sequences. All though the margins and contacts to these flows are commonly gold mineralized,

the flows themselves are very seldom gold mineralized. The complete absence of potassium

feldspars in these rocks will shift them into dacitic fields on an IUGS classification diagram.

Where they actually lie within this diagram will largely be a function of the estimated total silica

content, plate 4.

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a b

c.

Plate 4. Coherent intermediate flows. On plate 4a, a macroscale image taken at a 30x with a 15 mm field of view,

illustrates the dominant textural characteristics of this volcanic rock. The rock unit is decidely non-porphyritic and

contains a very fine grained, quenched grey matrix which locally embays small chloritie – pyrite grains, plate 4b.

The images are from sample MD 13 – 19 @ 97.4. The near complete absence of potassium feldspar within these

flow sequences will strongly suggest that these flow units will lie in dactitic fields using an IUGS compositional

plot, plate 4c. For detailed destriptions see the appropriate Appendix description.

Re-worked Intermediate Crystal Tuffs or Plagioclase Phyric Intermediate Volcaniclastics (MD

13 – 21 @ 434.6 m).

This rock unit is commonly cored deep in the stratigraphic section in the Mirado mine area. In

hand specimen it appears as a homogenous, competent rock unit with only rare evidence of small

fragments or clasts. When noted, phenocrysts in hand specimen appear to be abraded or sub-

rounded and significant levels of transport are suggested.

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Those textural features are also noted in thin section. The abundant plagioclase grains are

commonly broken and sub-rounded and a chlorite foliation surface, not mafic phenocrysts, is

defected around these grains. The rock unit may either be interpreted as a plagioclase phyric

volcanic wacke or as a plagioclase phyric crystal tuff.

a b

Plate 5. Plagioclase phyric volcaniclastics – crystal tuffs. On the detailed macroscale image, plate 5a, the partially

annealed, rounded nature of both quartz and plagioclase grains are noted, field of view plate 5a, 15mm. The abraded

nature of plagioclase grains is superbly demonstrated on plate 5b. Detailed descriptions are contained in the relevant

Appendix descriptions.

Felsic Ash Tuffs and Banded Semi-massive Sulphides (MD 13 – 26 @ 309.8m)

During the construction of the initial stratigraphic logs these rocks were interpreted as either

cherty tuffs or as felsic ash tuffs both of which were hosting semi-conformable semi-massive

sulphide bands. The presence of very small detrital quartz grains within the yellow green sericite

rich zones would suggest that the interpretation of this unit as a fine grained felsic ash tuff is the

preferred interpretation. The unit also supports early sphalerite plus or minus chalcopyrite bands

which appear to be semi-conformable to compositional layers. The presence of gold grains,

entirely embayed within massive sulphide bands would suggest that gold in this system is early

and intimately associated with massive sulphide.

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a b

Plate 6. Banded massive sulphide – felsic ash tuff protolith. Coarse dark grey early sphalerite bands are forming

parallel to pale green sericitic ash tuffs. For detailed photograph descriptions refer to the relevant Appendix entry.

b. Intrusive Rock Units:

Dioritic Sub-volcanic Intrusions (13 – 16 @ 85.2 m, 13 – 27 @ 72.35 m)

Rocks which are interpreted as dioritic intrusions are noted in this sample suite. These rocks

invariably have very high, to crowded, plagioclase phenocrysts. Most significant is the

observation at the thin section scale that these larger matrix phenocrysts are also embayed in a

matrix which appears to have a crystalline to sub-crystalline form. The quenched matrices

associated with flow sequences are absent and, unlike crystal tuffs, most of the plagioclase grains

are highly euhedral, unbroken and not transported.

The majority of the early plagioclase phyric intrusions in drill core, in contrast to the numerous

syenitic intrusions at Mirado, have a complete lack of primary orthoclase. The absence of

orthoclase will shift these rocks to diorite fields on an IUGS classification, Plate 7.

a b

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Plate 7. Dioritic Sub-volcanic intrusions. The abundant plagioclase phenocrysts noted at both the macroscale and

microscale, plate 7a and 7b, strongly support an interpretation of this rock unit as an intrusive, not extrusive mineral

phase. The absence of primary potassium feldspars and the observation that the sample contains less than 5% free

quartz requires that in an IUGS classification these samples will lie in dioritic field, plate 7c. Full text descriptions

refer to the relevant Appendix entry.

Definition of the regional metamorphic field

Mafic volcanic or volcaniclastic rocks in this sample suite contain the following regional

metamorphic mineral assemblages:

sericite-chlorite-epidote-chloritoid +/- quartz

In high magnesium and alumina rich rocks chloritoid will begin to be formed at approximately

300 oC at about 3.5 kbar.

Metamorphic biotite is never identified and the absence of biotite suggests that the transition

from low-mid greenschist to mid-upper greenschist, which is defined in part by the “chlorite out

– biotite in” isograd, about 420 oC at 3.5 kbar, is never reached. Metamorphic albite was not

identified in these samples and the shift between low An albite (An17) and high An albite, the

perisiterite gap which also signifies the transition between greenschist and amphibolite

metamorphism, is never attained. The absence of phenrite-pumpellyite in these rocks requires

that they lie above sub-greenschist metamorphic fields. In tota,l these data suggest that the

Mirado gold occurrence has experienced only lower greenschist metamorphic fields likely in the

range 4.0 – 4.5 kbar and 375 – 400 oC, plate 8.

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Plate 8. Metamorphic PT Space Mirado Rocks. On this PT grid, the Mirado rocks will plot in lower greenschist

fields. The general field area is indicated by the red oval and “MPT”.

Documentation of the hydrothermal alteration assemblages

The 11 Mirado polished thin sections contain two predominant alteration assemblages which are

related to either late gold – copper veins and early polymetallic gold rich massive sulphides. In

detail:

1. Sericite – quartz – iron carbonate – chlorite : Early VMS Related Alteration.

This alteration form characterizes the nature of rock alteration associated with early

compositional parallel bands and aggregates of sphalerite – chalcopyrite – pyrite and gold. It is

important to note that the presence of discrete gold grains associated with sphalerite or

chalcopyrite and not quartz, suggests that the Mirado massive sulphide zones, e.g. the North

Zone, are true precious metals enhanced massive sulphide bodies. The dominance of sphalerite

and iron carbonate as the principle sulphide and gangue alteration form suggests that this sample

has been collected from a volume of rock which has seen only lower temperature and distal

hydrothermal fluids associated with the formation of these sulphide phases.

2. Quartz – chlorite –epidote - sericite +/- gold/copper: Late Gold Related Alteration.

Most of the visible gold documented at Mirado has a spatial relationship with small quartz-

chlorite extensional veinlets. Gold grains may be contained within pyrite grains but these grains

have always been re-mobilized into this position along very small microfractures.

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Sulphide and vein paragenesis

The general paragenetic relationships between the several sulphide and gold phases identified

inthis sample suggests:

Early precious metals enhanced VMS type paragenesis:

sphalerite gold pyrite chalcopyrite hematite

gangue mineralogy: quartz/sericite fe/mg carbonates chlorite calcite

Late auriferous vein type paragenesis:

pyrite chalcopyrite gold hematite

gangue mineralogy: quartz chlorite epidote calcite

One sample e.g. MD 13 – 14 @ 318.6 m was initially selected from an assay interval, 318.4 –

319.0 m which assayed 91.9 g/t Au. Although gold grains are identified in this interval, the

very fine grained nature of these grains, ranging from 5 – 20 microns and probably averaging

less than 5 microns, may suggest that gold is also reporting to the lattice of chalcopyrite. Gold in

solid solution with copper may form minerals such as, kostovite (CuAuTe4); auricupride

(AuCu3).

a b

Plate 9. Gold Grains. On plate 9a, gold grains in early sulphide phases are associated with fine grained masses of

chalcopyrite, sample 13 – 26 @ 309.8 m. These grains have a very limited association to secondary quartz. The

second style or form of gold mineralization is associated with small extensional quartz veins which post-date earlier

formed pyrite and have a close spatial association to secondary quartz, sample 13 – 03 @ 163.7 m, plate 9b. Detailed

descriptions are contained in the relevant Appendix entries.

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Structural characteristics

The petrographic data suggests:

1. Most of the rocks have a modest S1 or early metamorphic fabric. This fabric has no

rotational components and is formed from the alignment of sericite – chlorite.

2. Strong variability exists in the development of early rock strain, with no change in

metamorphic gradients. All rocks have a moderate to well-defined metamorphic fabric,

but rocks collected from the northern half of the study area e.g. MD 13 – 22 @ 49.6 m or

MD 13 – 26 @ 309.8 m have significantly higher rotational strains. This suggest that

planar high strain zones, which are discordant to the early S1 fabrics, are locally well

developed on the Mirado property.

3. In these samples, gold grains in veins, are forming in late extensional microveinlets and

fracture sets. In some cases, these extensional veinlets are forming discordantly and cut

earlier oblique-extension veinlets.

4. In a few samples, a late crenulation fabric post-dates the early metamorphic fabrics.

These are likely to be relatively minor and have only modest relevance to subsequent

exploration.

5. Early sulphide phases have been moderately to strongly re-crystallized. The clean

boundary contacts between various sulphide phases and the lack of a significant sulphide

phase as inclusions trapped in other sulphides suggest that the metallurgy would be quite

favorable. Problematic metallurgical conditions e.g. significant chalcopyrite inclusions in

sphalerite are not identified.

Interpretations – relevance to exploration data

The petrographic data would support the following general statements which may have

relevance to subsequent exploration on the Mirado occurrence:

1. The presence of gold in early zinc rich sulphide phases confirms earlier observations that

precious metals enriched massive sulphides will form an important target type within the

Mirado rock environment. All of the parameters involved in the search for this type of

deposit including a clear understanding of stratigraphic controls on the development of

VMS mineralized zones should be clearly defined.

2. The direct relationship of gold to sphalerite in early sulphide zones suggests that zinc

geochemistry in soils or tills may be a useful and reliable indicator of gold bearing

massive sulphides.

3. The strong association of fe-mg carbonates with precious metals enhanced massive

sulphides suggests that geochemical indicators for Mg, may have positive correlation to

the formation of early gold and sulphide mineralized zones.

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4. The absence of arsenical sulphide phases, antimony, stibnite etc. suggests that the late

gold event, typically associated with small extensional veinlets will not be traced by

arsenic, antimony, mercury etc. in surface soils or tills. Late gold mineralized events are

likely best identified by copper and gold in surficial medium.

5. Late gold, vein related, gold mineralized zones are formed in rocks which have very

modest strain fabrics. Early gold mineralized zones are associated with subtle extensional

vein arrays which have previously been suggested to have dilatant zones which are

largely controlled by broader scale lithologic controls.

6. Neither magnetite nor pyrrhotite are significantly associated with either early or late gold

mineralized zones. In these samples, hydrothermal magnetite is never identified making

a direct correlation between magnetic highs and gold mineralized zones problematic at

best.

Jim Oliver, Ph.D., P.Geo.

Kamloops, B.C.

May 9, 2014.

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APPENDIX I.

PETROGRAPHIC DESCRIPTIONS.

Sample Number Page

MD 13 – 03 @ 163.7 m. ……………………………………………………………………. 15

MD 13 – 09 @ 176.1 m ……………………………………………………………………. 21

MD 13 – 13 @ 31.0 m ……………………………………………………………………… 27

MD 13 – 16 @ 85.2 m………………………………………………………………………. 31

MD 13 – 19 @ 97.4 m ……………………………………………………………………… 36

MD 13 – 21 @ 434.6 m …………………………………………………………………….. 41

MD 13 – 22 @ 49.6 m …………………………………………………………………….... 45

MD 13 – 26 @ 309.8 m ……………………………………………………………………. 49

MD 13 – 27 @ 72.35 m ……………………………………………………………………. 55

MD 13 – 29 @ 20.7 m ……………………………………………………………………... 59

MD 13 – 14 @ 318.6 m ……………………………………………………………………. 64

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Sample Number: 13 - 03 @ 163.7m

a

b

Plate 10. Macroscale Images DDH 13 – 03@ 163.7m. The macroscale image has length of 40 mm and has been

cut and stained for secondary potassium feldspars, plate 10 a. The detailed macroscale image, 10b, has been taken at

a magnification of 40x and has a field of view of 12 mm.

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Protolith – Rock Name: Semi-massive Sulphide Vein

Alteration Assemblage: quartz-sericite-pyrite +/- epidote

Macroscale Textural and Morphological Characteristics: The sample has been selected from

a high sulphide veinlet with visible gold. The percentage of protolith versus discordant vein

types in this sample is very limited. As a result, protolith determination based on the small

volume of preserved protolith, is challenging. Relevant macroscale geological characteristics

include:

The sample contains a cm scale pyritic veinlet which is trending discordantly through a

fine grained, strongly sericitized protolith which may contain a residual plagioclase

phenocrysts.

The highly pyritic veinlet in this sample is cut by a series of sub-mm quartz veinlets

which are forming approximately orthogonal to the orientation of the pyrite vein margins.

Small gold grains are visible in this sample. Most of these grains are forming within the

margins of sub-mm quartz cyrstals.

Pyrite show no significant recrystallization or re-mobilization.

The pyrite veinlet is cutting a fine grained bleached, creamy with volcanic protolith

which at the macroscale is of in-determinant origin. The veinlet lacks any significant

alteration halo.

No base metal phases and no oxide phases are recognized.

The sample contains no evidence of secondary potassium feldspar.

Microscale Mineralogical Characteristics:

Primary Mineralogy

Mineral Abundance Grain Size

Quartz 15 - 17% <0.2 mm

Zircon trace 0.1 mm

Secondary Mineralogy


Quartz 12 - 14% 0.2 – 1.25 mm

Sericite 18 - 20% < 0.2 mm

Epidote 3 – 4% 0.15 – 0.35

Fe-mg carbonate 1.0 – 1.5% <0.15 mm

Pyrite 40 – 44% 0.15 – 4.0 mm

Gold > 100 grains < 0.05 – 0.2 mm

Pyrrhotite trace < .15 mm

Chalcopyrite trace < 0.15 mm

Hematite trace < 0.1 mm

Fluorescence: The sample contains no fluorescent mineral grains.

Magnetic Susceptibility (SI units x 10-3

): 0.023

General Petrographic Notes:

Primary Mineral Grains

Quartz: The matrix of the sample contains very small anhedral quartz grains. Most of these

grains have slightly felted or blurred margins and have been significantly overprinted by felted

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sericite masses. The sample matrix is non-porphyritic and all of these grains are present as fine

grained matrix crystals.

Zircon: The sample contains a single zircon grain. The grain is euhedral and although it is

entrained within a small quartz microveinlet it is primary in origin.

Secondary Mineral Grains:

Quartz: Secondary quartz forms approximately 15% of the sample. Secondary quartz is noted as:

The dominant gangue mineral in discordant quartz veinlets.

As small isolated grains which flank disseminated pyrite grains.

These grains are effectively devoid of inclusions and are typically unstrained with no evidence of

undulose extinction.

Sericite: Fine grained sericite masses are identified in two principle resident sites:

Throughout the matrix of the sample, sericite may outline and or pseudomorph either

larger plagioclase phenocrysts or small tuffaceous clasts. The vast majority of sericite in

the sample is of this variety.

Sericite within small discordant quartz veinlets. In this resident site, sericite is

subordinate to either quartz or epidote, but is often closely spatially related to epidote

grains.

Epidote: Epidote, like sericite, is documented as:

Forming a medial line, to small extensional veinlets. Most of these veins are syntaxial in

origin.

Forming an immediate rind to small pyrite grains which are disseminated throughout the

matrix of the sample.

Fe-Mg Carbonate: These grains are present solely as small anhedral aggregates within the quartz

microveinlets which cut this sample.

Pyrite: Pyrite is contained within the small pyritic microveinlet in this sample. These are large,

uniform euhedral pyrite grains containing only very minor quartz grains. The grains exhibit no

evidence of compositional zoning.

Gold: Gold grains are abundant in this sample and are characterized by:

They are invariably associated with secondary quartz – epidote microveinlets.

They are not associated with any other sulphide phases.

When identified internally to larger pyrite grains they are always noted along small

discontinuities within these samples.

Gold grains have locally been re-mobilized into “gold only” microfractures.

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Pyrrhotite: Pyrrhotite is identified as very small inclusions internal to pyrite grains.

Chalcopyrite: Chalcopyrite grains, like pyrrhotite, are noted solely as inclusions within pyrite

grains. Stable contact relationships suggest that pyrite – chalcopyrite and pyrrhotite are all stable

and likely forming contemporaneously.

Hematite: Hematite occurs only as very small rinds to pyrite grains and are in general very rare.

This sample is effectively unoxidized.

Structural Characteristics:

The sample has two relevant structural characteristics:

All quartz within the small veins has very low strain characteristics. There is a complete

lack of undulose extinction.

Quartz veinlets in this sample are growing at an orientation of approximately 60 degrees

to the pyrite vein margins. This suggests that pyritic veinlets are very small shear related

veinlets which are cut by late quartz extensional veinlets.

Plate 11. Protolith textural characteristics. The rock matrix consists of abundant fine grained sericite (s) grains

which may locally outline rectangular, possible primary plagioclase phenocrysts. The black opaque mineral grains

are pyrite. Transmitted cross polarized light, 25x.

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a

b

Plate 12. Gold – pyrite –quartz vein relationships. An anastomosing quartz veinlet has crystal orientations

compatible with extensional strain fields. The core of the vein is lined with epidote (e). Gold (au) grains are

scattered throughout the quartz and are never identified solely as inclusions in pyrite. Plate 12 a, transmitted cross

polarized light, 25x, plate 12b, reflected light 25x. Both plates, identical fields of view.

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Plate 13. Detailed gold grain characteristics. The sample contains greater than 100 gold (au) grains. These are

most often located in the interiors of quartz veinlets or occasionally present within microscale discontinuities within

pyrite (py) grains. In this thin section, no other sulphide grains are noted and gold is occurring as free mineral grains.

Average gold grain size in this field of view would be in the 20 to 50 micron range. Reflected plane polarized light,

100x.

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Sample Number: 13 – 09 @ 176.1m

a

b

Plate 14. Macroscale images Sample 13 – 09 @ 176.1 m. The hand specimen macroscale block is approximately

40 mm in length, plate 14a. The detailed macroscale image has a field of view of 15 mm, 30x, plate 14b.

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Protolith – Rock Name: Intermediate Mg Rich Lapilli Tuff

Alteration Assemblage: sericite-chlorite-chloritoid-quartz (metamorphic assemblage)

Macroscale Textural and Morphological Characteristics: The sample has been cut from a

mottled green fragmental. Highly elongate, cm scale darker green fragments are supported or

embayed against a light apple green matrix. Additional observations include:

The sample matrix give a weak response to the application of warm 10% HCl acid. The

matrix of the rock contains low levels of fe-mg carbonates. Ca-carbonates are noted

flanking euhedral pyrite grains. Chalcopyrite is not recognized.

The sample contains abundant euhedral pyrite grains which are forming parallel to the

dominant flattening fabric. Some of these grains are forming incomplete or irregular cm

scale lamella; others are present as random uniform disseminations.

Cream-green portions of the matrix contain a significant proportion of pale sericite

grains.

Fragments in this sample have elongate, and commonly highly feathered margins. They

also appear to have a higher percentage of a dark green elongate mineral grains. This is

either actinolite or edge on views of biotite. These fragments are unlikely to be a function

of rock alteration and likely represent true mafic fragments.

The sample may contain, very small, 0.15 mm, rounded to slightly abraded quartz grains.

Calcite plus or minus minor quartz grains may form pressure shadows adjacent to larger

pyrite grains.

The rock has a significant flattening fabric. This fabric shows no rotational components

and is likely an early regional metamorphic fabric.


Primary Mineralogy


Quartz 25 – 29% 0.1 – 0.3 mm



Sericite 20 – 24% < 0.1 – 0.25 mm

Chlorite 30 – 34% <0.1 – 1.5 mm

Chloritoid 2.5 – 3.0% 0.1 – 0.35 mm

Quartz 3.0 – 3.5% <0.1 – 0.4 mm

Fe-mg carbonate 1.5 – 2.0% < 0.15 mm

Calcite 0.25 – 0 .4% < 0.15 mm

Pyrite 3.0 – 4.0% 0.15 -1.75 mm

Hematite 0.25 – 0.75% < 0.15 mm

Chalcopyrite trace 0.15 mm

Pyrrhotite trace < 0.15 mm



): 0.040

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Quartz: Primary quartz grains from much of the sample matrix. These are very small grains

which have been extensively overprinted by fine grained elongate sericite lathes. The grains are

effectively absent from the green clastic fragment rich area.


Sericite – muscovite: Very fine grained sericite-muscovite grains occur in both mafic rich and

mafic poor portions of the sample. These grains also form the dominant foliation surface. Early

sericite grains are commonly bent and crenulated. This late but very weak cleavage also appears

to be formed by the alignment of sericite grains.

Chlorite: In this sample fine grained chlorite aggregates outline mafic clasts. Coarser grained

chlorites are also forming in the pressure shadows adjacent to pyrite grains. The pale greenish

birefringence patterns of these grains suggests that they are Mg-Al chlorites.

Chloritoid: The fine grained, elongate, green black lathes which are disseminated throughout this

sample are chloritoid and not actinolite or biotite as suggested by the macroscale descripton. This

mineral grain may be distinguished from other sheet silicates by its length fast elongation, its

relief, by its significant blue-green pleochrosim and by sporadic twin plane development.

Chloritoid is most common in this rock unit within the darker green more mafic appearing clasts.

Quartz: Secondary quartz occupies two specific resident sites in this sample:

As the dominate gangue mineral in pre S1 quartz veins.

As the dominant gangue mineral forming pressure solution shadows to pyrite grains.

Fe-mg and Ca Carbonates: Small carbonate grains are documented throughout the matrix of the

sample. Most of these grains are likely Fe-Mg carbonates. Scattered calcium carbonate grains are

sometimes noted forming within the interstices to larger quartz grains formed in small veinlets.

Pyrite: Pyrite is the dominant sulphide phase. It appears to present as a porphyroblastic mineral

grain within the sample. These strongly euhedral grains are disseminated throughout the rock but

are preferentially developed in green clastic fragments. Occasionally these grains are may be

organized into narrow loose lamella.

Hematite: Hematite is typically identified as elongate lathes and occasionally as small aggregates

which are forming in the plane of the foliation surface. It is not present as either veins or

aggregates.

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Chalcopyrite: Rare, 0.15 mm long chalcopyrite grains are noted in this sample either as minor

disseminations or forming a rind to euhedral pyrite. Chalcopyrite is present as a minor accessory

or trace mineral.

Pyrrhotite: Pyrrhotite grains are sometimes noted as small inclusions within the larger pyrite

grains. It is not identified as matrix disseminations.

Structural Characteristics:

The sample displays a number of distinctive structural characteristics:

The sample has strong non-rotational penetrative, S1 (?) fabric. This fabric has been

further deformed by a late kink style S2 (?) foliation.

The absence of quartz grains internal to green fragment areas strongly suggests that the

fragments are real and are not simple alteration fronts.

Chlorite and chloritoid may have different metamorphic pressure temperature paths.

Chlorite appears, like sericite to form part of the dominant S1 surface. Most commonly

chloritoid grains are overprinting that early metamorphic fabric.

S1 fabrics are discordant, at low angles to green clasts. This suggests that clasts pre-date

S1 fabrics further suggesting that clasts are primary in origin.

Plate 15. Protolith Characteristics. The elongate green clasts are chlorite (c) dominant and generally lack matrix

quartz (q) The sample matrix is composed of abundant, fine grained anhedral quartz. A sericitic (s) cleavage cuts

obliquely through the mafic fragments. Transmitted, cross polarized light 25x.

25

a

b

Plate 16. Chloritoid – chlorite matrix mineralogy. The sample contains abundant chloritoid (ct) grains which

appear orange-yellow under transmitted cross polarized light (plate 16a) or have a distinctive blue-green

pleochrosim under plane polarized (plate 16 b) light. These grains are embayed in a field dominated by secondary

chlorite (c) which also supports scattered pyrite (py) grains. Plate 16a, transmitted cross polarized light, plate 16b

transmitted plane polarized light.

26

a

b

Plate 17. Sulphide – silicate relationships. In this sample, crowded euhedral pyrite grains are preferentially

forming within chloritized (c) mafic clasts. Pyrite may also be forming narrow incomplete lamella. Scattered sericite

(s) grains are noted throughout the matrix. Plate 17a, transmitted cross polarized light, 25x; plate 17b, reflected

plane polarized light 25x. Identical fields of view in both plates.

27

Sample Number:13 – 13 @ 31.0 m

a

b

Plate 18. Macroscale images sample 13 – 13 @ 31.0 m. The stained off cut is approximately 40 mm long (plate

18a) and the detailed macroscale image has a field of view of 12 mm taken at 40x, plate 18b. The detailed

macroscale image has a crowded crystalline matrix which suggests that the sample has been cut from a dioritic

intrusion or alternatively from a crystal tuff. . The blurred grey matrix grains may represent secondary quartz.

28

Protolith – Rock Name: Intermediate Crystal Tuff

Alteration Assemblage: sericite-epidote-chlorite

Macroscale Textural and Morphological Characteristics: The sample carries abundant

medium grained, sericitized plagioclase phenocrysts which occur throughout the matrix. The

matrix itself appears anhedral. At the macroscale, the rock is either a fine grained porphyritic

dyke or a crystal tuff. Relevant hand specimen textural and morphological features include:

The sample matrix contains abundant sub mm scale, apple green sericitized plagioclase

phenocryts. Most of these average about 0.5 – 1. 0 mm. None of these appear to be

aligned to the regional S1 fabric.

The sample gives a weak response to the application of warm 10% HCl acid. Much of

this response comes from fe-mg carbonate grains which have a close spatial association

with sausseritized plagioclase phenocrysts.

No compositional layers are identified.

Free quartz in the matrix of the sample, or primary quartz phenocrysts, is not identified.

The sample contains an abundant dark green, possible chlorite rich matrix

No significant discontinuities, or discordant vein sets, are identified

Pyrite is occurs as a few random disseminated euhedral grains. No other sulphide phase

are identified.


Primary Mineralogy


Quartz 17 - 19% 0.15 – 0.25 mm

Plagioclase 10 - 12% (35 – 40%) 0.2 – 1.0 mm



Epidote 12 - 15% 0.1 – 0.2 mm

Sericite 26 - 29% < 0.15 mm

Chlorite 15 - 18% 0.1 – 0.3 mm

Quartz 3 - 4% 0.1 – 0.25 mm

Fe-mg carbonates 2.5 – 3.0% < 0.1 mm

Pyrite 0.5 – 0.75% < 0.1 – 0.5 mm

Pyrrhotite trace 0.1 mm

(bracketed numbers indicate estimated mineral percentages prior to rock alteration)



):0.053


Primary Mineral Grains:

Quartz: Primary quartz occurs throughout the matrix of the sample most often as very small,

generally 0.15 mm or less, mineral grains. Quartz is not recognized as a phenocryst phase.

29

Plagioclase: Much of the sample matrix consists of equant plagioclase grains which have often

been extensively replaced by secondary sericite. Primary twin plan orientations may not be

determined from these mineral grains.


Epidote: Small euhedral to anhedral epidote grains form irregular aggregates and may commonly

define well defined outlines of blunt pyroxene (?) grains. Epidote aggregates are often noted

forming in association with sericite replaced plagioclase grains.

Sericite: Small sericite lathes replace the majority of the plagioclase phenocrysts noted in this

sample. Sericite is not forming a well-defined penetrative foliation surface in these samples.

Chlorite: Chlorite occurs as fine grained matrix disseminations and aggregates throughout this

sample. Chlorite is typically non-aligned and has not significant vein association.

Quartz: Secondary quartz is identified as small matrix disseminations. These grains may either

be recognized as mall uniform matrix disseminations and or as rare aggregates and

disseminations. Secondary quartz is also noted as a infill to very small microveinlets.

Fe- mg Carbonates: Iron carbonate grains are noted throughout the matrix. These grains are

identified in discrete discontinuities and may have a weak preferential spatial relationships with

pyrite grains.

Pyrite: Pyrite occurs as minor disseminations and aggregates. Most of these grains have the

strongly embayed margins which track and capture numbers inclusion.

Pyrrhotite: Pyrrhotite is noted as discrete inclusions within larger pyrite grains. It is not

identified in isolation of pyrite.

Structural Characteristics: The sample lacks well developed penetrative fabrics and no planar

discontinuities are identified.

30

a

b

Plate 19. Dominant phenocryst phases. Strongly epidote (e) altered phenocrysts (pyroxene (?) in plate 19a and

plagioclase in plate 19b are embayed in a fine grained, anhedral quartz (q) rich matrix. Rectangular strongly

sericitized (s) forms throughout the matrix are most likely altered plagioclase. Transmitted, cross polarized light,

25x.

31

Sample Number: 13 – 16 @ 85.2 m

a

b

Plate 20. Macroscale images sample 13 – 16 @ 85.2 m. On plate 20a, the sample length is approximately 40 mm.

On the detailed macroscale image, plate 20b, the sample length is 15 mm and the image has been shot at a

magnification of 30x.

32

Protolith – Rock Name: Dioritic Sub-volcanic Intrusion.

Alteration Assemblage: sericite - epidote-calcite-chlorite

Macroscale Textural and Morphological Characteristics: This sample is unique in the

presence of relatively large mm to cm scale zoisite-clinozoisite – carbonate aggregates which

locally have the appearance of a vesicular infill. The sample has the following relevant

macroscale textural and morphological characteristics:

The pale yellow cream aggregates which are formed throughout the sample are

compound mineral assemblages and contain both carbonate-epidote +/- quartz

aggregates.

Pale cream aggregates are nucleating around darker green chlorite rich cores.

Net sulphide content in this sample is quite low. A few disseminated pyrite grains are the

sole sulphide phase. These grains are noted as minor disseminations and never in

compositional lamella or in discordant veinlets. No other sulphide grains are identified.

The matrix of the sample may contain a low percentage of very fine grained, less than 0.1

mm quartz grains.

Sporadic tan to flesh colored leucoxene grains are locally identified.

The sample lacks obvious fragments and contains no primary compositional layers.


Primary Mineralogy


Plagioclase 30 - 35% (50 – 60%) 0.25 – 2.0 mm



Calcite 15 – 18% 0.2 – 1.5 mm

Sericite 12 -15% < 015 – 0.4 mm

Chlorite 15.5 – 18.5% 0.15 – 0.25 mm

Epidote 10.5 – 12.5% 0.1 – 0.3 mm

Pyrite 0.5 – 0.75% 0.15 – 0.5 mm

Hematite 0.15 – 0.3% < 0.15 mm

(bracketed numbers indicate estimated mineral percentages prior to rock alteration)

Fluorescence: The sample contains three light blue fluorescent grains. These grains are likely

activated carbonate mineral grains.


): 0 .169



Plagioclase: The dominant primary mineral grain is in this sample is plagioclase. These

relatively large phenocrysts are embayed within a sub-crystalline matrix which is also composed

dominantly of plagioclase. Fine grained free quartz is not identified.

33


Calcite: Secondary calcite occurs in two principle resident sites in this sample. These grains are

noted as either:

Forming the central portions of zoned calcite – epidote irregular oval shaped aggregates.

Found as amorphous fine grained disseminations throughout the rock matrix.

Sericite: Much of the sericite in this sample is selectively replacing the cores of the large

plagioclase phenocrysts. Sericite is also noted as relatively non-aligned, small mineral grains

throughout the rock matrix.

Chlorite: Chlorite, along with sericite, is noted as persistent matrix replacements and infill. It

may also be associated with epidote within amygdaloidal shaped aggregates. The birefringence

properties of chlorite in this sample suggests that it is an Mg chlorite.

Epidote: Epidote forms the external “rind” to the zoned carbonate-chlorite-epidote aggregates

producing a spotted textural overprint to this sample. It is also occasionally noted as small

disseminated matrix grains.

Pyrite: Pyrite occurs as minor disseminated grains throughout this sample. It does not have a

strong association with the amygdaloidal alteration aggregates and is not associated with

discordant veins or veinlets. The inclusion rich form of these grains strongly suggests that they

are secondary in origin.

Hematite: Hematite occurs as fine grained, non-aligned, aggregates and disseminations

throughout the matrix of the sample. These grains are not forming after pyrite but appear to

represent an oxide rich probable metamorphic phase.

Structural Characteristics: This sample lacks strong penetrative fabric development. The very

crystalline and interlocked nature of the matrix plagioclase strongly suggests that it represents an

intermediate composition, monzonite to monzodiorite, potentially a sub-volcanic intrusion.

34

a

b

Plate 21. General textural relationships, interlocked mineral crystals. The crystal forms noted on this plate

suggest that the rock is a high level intrusion and not a flow sequence. Crowded plagioclase (p) crystals are

identified both as phenocrysts and as crystalline, interlocked matrix materials. Minor calcite (cc) and sericite grains

are noted and sericite is breaking down plagioclase. Carbonate occurs in small microveinlets and occasionally with

sericite. Plate 21, transmitted plane polarized light, 25x, plate 21b, transmitted cross polarized light, 25x.

35

Plate 22. Nature of amygdaloidal aggregates. The pale greenish-cream oval shaped forms noted in the hand

sample are well displayed in this photomicrograph. These mineral aggregates represent a reaction front which grades

from a calcite (cc) rich core zoning to an epidote (e) rich rind. These aggregates appear to be replacing both the rock

matrix and the larger plagioclase (p) phenocrysts. Transmitted cross polarized light 25x.

Plate 23. Pyrite Grains. Subhedral pyrite grains containing abundant inclusions are noted in this photomicrograph.

These textures are common in late secondary sulphide grains. Reflected plane polarized light 50x.

36

Sample Number: 13 - 19 @ 97.4m

a

b

Plate 24. Macroscale images sample 13 - 19 @ 97.4m. Sample length of the off-cut block in plate 24a is 40 mm.

In the detailed macroscale image, plate 24b, the field of view is 15 mm, taken at a magnification of 30x.

37

Protolith – Rock Name: Intermediate Flow

Alteration Assemblage: sericite-chlorite-carbonate-pyrite

Macroscale Textural and Morphological Characteristics: The sample has the following

distinctive diagnostic and textural characteristics:

The sample has been cut from a pale green, fine grained volcanic rock. This sample lacks

obvious free quartz grains and based on the color index, 15 – 20, is likely representative

of a dacitic flow.

The sample matrix is very fine grained, quenched and consists of pale cream – grey semi

translucent quartz-feldspar aggregates.

The off-cut block has not stained positive for potassium feldspar. The fine grained

quenched matrix appears to be composed of aggregates of fine grained quartz plus or

minus plagioclase.

A significant percentage of calcite, all of which is coring mm scale chlorite aggregates or

clots, is identified.

Chlorite is documented as disseminated mm scale aggregates throughout the matrix.

These grains appear to be replacing primary mafic mineral grains.

No evidence exists for primary flow laminations.

Pyrite is the sole sulphide phase itoccurs as small disseminations throughout the rock

matrix. It is not identified within discordant vein sets or planar lamella.

The overall greenish coloration of the matrix is suggestive of high secondary sericite

contents.

Very rarely, cream colored less than 0.75 mm, phenocryst casts or outlines are noted.

These appear to be elongate, highly altered plagioclase grains.


Primary Mineralogy


Quartz 25 – 30% 0.1 – 0.2 mm



Sericite 30 -34% 0.15 – 0.4 mm

Chlorite 12 – 15% 0.2 – 1.0 mm

Calcite 8 – 10% <0.2 – 0.4 mm

Epidote 6 – 8% 0.15 – 0.35 mm

Quartz 0.5 -1% 0.2 – 0.35 mm

Pyrite 1 – 1.5% 0.2 – 2.0 mm

Hematite 0.5 – 0.75% < 0.15 mm





): 0.031

38



Quartz: The small quartz grains in this sample are noted solely in the matrix of this sample.

These grains appear as very fine grained quenched aggregates which are embayed in masses of

fine grained sericite.


Sericite: The matrix of this sample contains abundant secondary sericite. Sericite is forming,

along with quartz, as an important matrix mineral grain constituent. It is found most often as

non-aligned, fine grained radiating mineral aggregates. Sericite compositional layers or sericite

as a vein infill is not identified.

Chlorite: Secondary chlorite grains are commonly medium green in color and are likely Mg

dominant mineral grains. They have a spatial association with the formation of secondary pyrite,

epidote and calcite. The grains often form well developed pressure shadows to larger pyrite

crystals.

Calcite: Calcite grains have a distinctive spatial association with secondary chlorite aggregates.

Secondary calcite is identified as both rinds and core zones to chlorite aggregates. It is not

identified as discordant vein infill. Calcite has a weaker spatial association to pyrite than do

chlorite grains.

Epidote: Small epidote crystals have an intimate association with, and are often embedded in,

secondary calcite grains. The grains are poorly formed and are often obscured by a dark grey

amorphous mineral grain, likely calcite.

Quartz: Secondary quartz grains are only identified forming as pressure shadows to larger pyrite

grains. These grains have weak undulose extinction patterns and in this sample are never

identified in discordant vein sets.

Pyrite: Secondary pyrite occurs as small irregular disseminations throughout the matrix of this

sample. They contain abundant, dominantly silicate inclusions. The formation of these inclusions

is strong petrographic evidence supporting an interpretation that these grains are secondary in

origin.

Hematite: Very small hematite grains are identified as discrete matrix disseminations and never

formed in association with pyrite. The style and form of these grains suggest that they may

represent one of several alteration components related to the breakdown and replacement of

primary mafic mineral phases.

39

Chalcopyrite: Chalcopyrite is documented only as small irregular inclusions within the larger

pyrite grains. Chalcopyrite has not been identified in any other resident site.

Pyrrhotite: Like chalcopyrite, pyrrhotite is only identified as minor inclusions within pyrite

grains. Volumetrically, pyrrhotite as an inclusions in pyrite occurs less commonly than

chalcopyrite as an inclusion to pyrite.

Structural Characteristics: This sample lacks any significant penetrative fabrics or primary

compositional layers. The development of undulose extinction patterns and elongate weakly

curvilinear quartz in pressure solution shadows to pyrite grains, suggests that these grains may

have been forming under weak rotational strains.

Plate 25. Secondary pyrite grains. The large secondary pyrite grains which are forming disseminated aggregates

throughout the field of view have the inclusion rich features which are characteristic of secondary pyrite. Reflected

light 25x.

40

a

b

Plate 26. Matrix characteristics, intermediate flow. The sample has the fine grained, quenched matrix which is

characteristic of extrusive volcanic rocks. Primary mafic mineral assemblages have been completely replaced by the

chlorite (c)-epidote (e) calcite (cc) aggregates. All matrix plagioclase has been replaced by fine grained sericite.

Plate 26a, transmitted plane polarized light, 25x; plate 26b, transmitted cross polarized light, 25x. Identical fields of

view, both plates.

41

Sample Number: 13 -21 @ 434.6m

a

b

Plate 27. Macroscale images sample 13 -21 @ 434.6m. The length of the stained off-cut block on plate 27a, is 40

mm. The field of view on the detailed macroscale image, plate 27b, is 15 mm at 30x magnification.

42

Protolith – Rock Name: Plagioclase Phyric Intermediate Volcaniclastic to Plagioclase

Phyric Crystal Tuff

Alteration Assemblage: sericite-chlorite-carbonate


moderately foliated medium grained, pale grey-green volcaniclastic or tuffaceous rock unit.

Relevant macroscale textural and compositional features include:

The sample matrix contains abundant euhedral to slightly sub-rounded plagioclase grains.

They have only weak to moderate alteration levels as even in hand specimen primary

albite lamella are visible.

The dominant foliation in this rock unit is formed by the alignment of chlorite mineral

grains. These grains are also noted as minor disseminations throughout the rock matrix.

A few scattered rounded to sub-rounded quartz phenocrysts are identified within the rock

matrix.

The sample contains no secondary or primary potassium feldspar. It has accepted no

cobalt nitrate stain following etching with HF acid.

The sample matrix contains light to moderate amounts of fine grained fe-mg to ca

carbonates. No carbonate minerals are associated with discordant veins or microveinlets.

The sample has low sulphide contents, pyrite is not identified.

Bleached, pale cream leucoxene grains, which are less than 0.25 mm, are scattered

throughout the matrix.


Primary Mineralogy


Plagioclase 45 - 50% (60 – 65%) 0.5 – 2.25 mm

Quartz 12 - 13% < 0.15 mm



Sericite 12 - 14% < 0.15 mm

Chlorite 12 – 13% 0.15 – 0.5 mm

Calcite 6 - 8% < 0.15 mm

Epidote 1.5 – 2.5% < 0.15 mm

Hematite 1.0 – 1.5% < 0.1 mm




): 0.052

43



Plagioclase: Much of the sample consists of abundant angular to sub-angular plagioclase grains.

Based on their twin plane orientations, these grains have variable An contents ranging from An40

to An70. Most of these grains are weakly to moderately overprinted by fine grained sericite.

Quartz: Quartz is never identified as euhedral grains or porphyritic phenocrysts. Quartz in this

sample is only noted as very fine grained matrix aggregates.


Sericite: Fine grained sericite is noted in two principle resident sites including:

As fine grained replacements of earlier plagioclase grains.

As fine grained and often weakly aligned to the dominant foliation surface sericite grains.

Chlorite: Chlorite grains are noted throughout the matrix of this sample. Chlorite occurs as

irregular feathered to irregular aggregates within the sample. Most of these grains have been

aligned to and form the dominant foliation surface.

Calcite: Calcite grains are identified as very small disseminated aggregates within the sample

matrix. Calcite lacks any preferred association to either chlorite or plagioclase matrix grains and

are associated with both mafic and felsic mineral grains within the sample matrix.

Epidote: Small epidote grains are preferentially associated with disseminated calcite grains

within the sample matrix. In this resident site, epidote along with calcite and chlorite represent

secondary mineral assemblages after primary mafic mineral phases.

Hematite: Small often lathe like hematite grains are noted throughout the matrix. These gains are

sometimes noted forming sphene type crystal forms and are likely forming after mafic mineral

grains or even after secondary leucoxene.

Chalcopyrite: Chalcopyrite is identified as very small aggregates and disseminations within this

sample. It has no vein association and association with the sole oxide phase, hematite.

Structural Characteristics: The sample contains no primary compositional lamella. The

alignment of chlorite grains defines the principle early, S1, fabric surface.

44

a

b

Plate 28. Matrix characteristics primary and secondary mineral grains. The matrix of the sample contains

abundant euhedral to slightly sub-rounded plagioclase (p) grains. These grains are locally abraded and demonstrate

some of the characteristics associated with transported or re-worked mineral grains. All quartz (q) in this sample

occurs as very fine grained matrix disseminations. Elongate wispy chlorite (c) aggregates form the principle

foliation surface. Plate 28a, transmitted plane polarized light, 25x, plate 28b, transmitted cross polarized light.

Identical fields of view in both plates.

45


a

b

Plate 29. Macroscale images sample 13 – 22 @ 49.6m. The length of the off-cut block on plate 29a, is 40 mm. The

detailed macroscale image has a field of view of 15 mm and has been taken at 30x, magnification, plate 29b.

46

Protolith – Rock Name: Mafic Lapilli Fragmental

Alteration Assemblage: chlorite-sericite-carbonate

Macroscale Textural and Morphological Characteristics: This sample has an exceptionally

well foliated matrix which contains abundant, flattened to weakly cuspate fragments. Relevant

macroscale features of this sample include:

The sample matrix contains abundant fine grained matrix calcite.

No secondary or primary potassium feldspars are identified in the sample matrix.

Very minor, < 0.5%, quartz grains are noted in this sample

Sporadic larger plagioclase phenocrysts are noted in this sample. These phenocrysts form

well developed strain markers with locally well-developed rotational fabrics are noted

proximal to these grains.

Two generations of chlorite is noted. One of these grain types forms dark green black

aggregate. A second form occurs as fine grained matrix dissemination and is pale to

lighter green in color.

A single 2 – 3 mm wide higher planar calcite vein is documented in the lower left hand

corner of this sample.

No sulphide grains are identified in this sample.

The sample matrix appears to contain a significant percentage of a fine grained pale

yellow cream oxide, possibly a leucoxene mineral grain.


Primary Mineralogy


Plagioclase 18 - 22% (15 – 20%) <0.2 – 1.0 mm



Chlorite 30 - 34% <0.1 – 0.4 mm

Sericite 15 - 20% < 0.2 mm

Calcite 12 - 15% < 0.2 mm

Quartz 6 - 8% < 0.2 mm

Hematite 1.0 – 1.5% < 0.15 mm



):0.059



Plagioclase: In this sample plagioclase grains are identified as partially corroded primary grains.

The margins of these grains have been corroded and removed by secondary processes including

those related to metamorphic re-crystallization. The grains do have recognizable albite twin

planes but preservation is not strong enough to determine albite contents.

47

Secondary Mineral Grains

Chlorite: Chlorite has two principle distribution sites:

As cuspate elongate aggregates and clusters, up to 1.0 cm in length, which are

dominantly chlorite forming after primary mafic mineral grains.

As a well-developed planar fabric, which along with sericite, forms the dominant

foliation surface.

In both resident sites, chlorite grains are medium green in color and likely Mg, not Fe, chlorites.

Sericite: Very fine grained sericite is identified in the cores of the heavily corroded plagioclase

crystals and also as a very fine grained sericite rich lamella. All of these grains are very small

and may form felted aggregates with chlorite.

Calcite: Scattered calcite grains are well documented in this sample. They occur as a late

overprint to plagioclase grains and are also found forming as single mm scale calcite rich vein.

This vein has no sulphide or oxide association.

Quartz: In this thin section, virtually all quartz is secondary in origin. It is found forming

pressure solution selvedges to the replaced mafic clasts in the sample. It is also documented as

small deformed isolated aggregates. All grains have well defined poly-sutured margins and show

evidence of extensive re-crystallization.

Hematite: Hematite occurs as small isolated grains throughout the matrix of the sample. These

are most commonly elongate mineral lathes which sometimes are forming in sub-mm aggregates.

The small size of the grains do not permit recognition of the mineral phase which they are

replacing.

Structural Characteristics: The sample has an exceptionally strong penetrative fabric and

larger phenocrysts exhibit well defined pressure solution shadows. None of the pressure solution

shadows exhibit rotational strain fabrics.

48

a

b

Plate 30. Textural characteristics of secondary mineral grains. The sample contains large plagioclase (p) grains

which are being corroded and replaced in the matrix of this sample, plate 30a. The dominant planar fabric, plate

30b, in the sample is composed of both fine grained sericite (s) and chlorite (c) aggregates. Transmitted plane

polarized light 25x.

49

Sample Number: 13 – 26 @ 309.8 m

a

b c Plate 31. Macroscale images sample 13 – 26 @ 309.8. The stained off-cut blank is approximately 35 mm in length,

plate 31a. The dark grey mineral phase is sphalerite and the brassy mineral phase is a combination of chalcopyrite

and pyrite, plate 31b. The cream colored disseminated aggregates on plate 31c are low iron sphalerite grains. The

detailed macroscale image, plate 31b, has a field of view of 15 mm taken at a magnification of 30x, plate 31c has a

field of view of 12 mm and has been magnified 40x.

50

Protolith – Rock Name: Felsic Ash Tuffs and Banded Massive Sulphides.

Alteration Assemblage: fe/mg carbonate-chlorite-sericite-sphalerite-pyrite-chalcopyrite +/-

sericite


semi-massive to massive sulphide band. The orientation of sulphide lamella within this band

strongly suggests that these lamella are forming approximately parallel to primary compositional

lamella. Relevant macroscale textural and morphological characteristics include:

The sample contains two varieties of sphalerite including dark brown to black iron rich

sphalerite grains as well as lemon yellow, pale semi-translucent low iron sphalerite

grains. Sphalerite is the dominant sulphide phase and probably exceeds 50% of this

sample.

Euhedral pyrite grains are also disseminate throughout the matrix of this sample. These

grains have been extensively annealed and re-crystalized.

Chalcopyrite is forming as a late rind to pyrite grains. These grains are not associated

with discordant quartz or vein sets.

The sample contains a single cm scale, medium to apple green sericite rich band. This

band is locally semi-conformable to sulphide lamella but has also been transposed

forming irregular discordant embayments into the sulphide grains.

Occasionally dark green chlorite lathes are forming marginal to euhedral pyrite grains.

Translucent, clear quartz grains are often embedded within the larger sphalerite grain

accumulations.

The matrix of the sample give a modest response to the application 10% HCl. These

grains have the style and form of fe-mg carbonates.


Primary Mineralogy


Quartz 5 – 6% 0.15 – 0.45 mm



Chlorite 5 – 6% 0.2 – 1.0 mm

Fe-mg carbonate 9 - 10% 0.2 – 1.0 mm

Calcite 1 – 2% 0.15 – 0.5 mm

Quartz 6 – 7% 0.2 – 0.75 mm

Sericite 7 - 8% <0.1 – 0.5 mm

Sphalerite 30 - 35% 0.2 – 5.0 mm

Pyrite 20 – 25% 0.1 – 2.0 mm

Chalcopyrite 3 – 4% 0.2 – 3.0 mm

Gold trace (12 grains) < 0.05 – 0.2 mm

Fluorescence: The sample contains not fluorescent mineral grains.


): 0.042

51



Quartz: Primary quartz grains are noted within cm scale bands and lamella within the matrix.

These grains are sub-rounded and often contain poly-sutured interiors. The grains are the sole

remaining indication that the rock protolith in this sample is a fine grained felsic ash fall.


Chlorite: Secondary chlorite grains are intimately associated with the semi-massive sulphide

bands noted in this sample. These grains may often flank or form well defined margins to both

individual sulphide grains and as envelopes to the larger bands or lamella.

Fe – Mg Carbonates: Dolomitic or ankeritic carbonates are forming an important gangue

component associated with the massive sulphide zones. Fe-mg carbonates are found as well

developed rhombs forming individual bands as well discrete disseminated grains within the

sample.

Quartz: Secondary quartz is identified in two principle resident sites including:

As the principle gangue mineral to sub mm scale microveinlets which are highly

discordant and may displace sulphide bands.

As small pits or inclusions within the sphalerite bands.

Sericite: Sericite occurs as very fine grained aggregates within the felsic ash tuff horizons noted

within this sample. Coarser sericite grains may sometimes appear with increasing frequency

towards the contacts of semi-massive sulphide bands and aggregates.

Sphalerite: Both iron rich and iron deficient sphalerite are the dominant sulphide phase in this

sample. Cm scale bands of sphalerite contain minor quartz-fe/mg carbonates and chlorite. Well

defined twin planes are occasionally noted within massive sphalerite grains.

Pyrite: Euhedral pyrite grains have annealed re-crystalized textures. About half of these grains

contain abundant fine grained inclusions, including both silicates and sulphide phases,

dominantly chalcopyrite. The remaining subset is effectively inclusion free.

Chalcopyrite: Chalcopyrite grains have a close spatial relationship to pyrite grains and often rim

pyrite grains. Occasionally chalcopyrite grains are noted as inclusions to pyrite grains.

Chalcopyrite is not identified as dissolution features with sphalerite or the sphalerite grains are

free of “chalcopyrite disease”.

Gold: The sample contains over a dozen gold grains. These grains range from less than 30

microns to greater than 200 microns. Many of these grains are forming completely isolated

52

embayments within the sphalerite with no gangue association. Other gold grains are in physical

contact with both sphalerite and quartz and may have an spatial relationship to early secondary

quartz.

Structural Characteristics: The sample has two significant structural features:

Early sulphide bands are off-set across narrow quartz microveinlets which are forming

approximately perpendicular to the sulphide bands.

Bands of coarser grained sericite, and the sphalerite bands themselves, may show low

angle discordant contacts. Microscale data suggests that the sulphides bands are also the

locus of early high strain zones.

Plate 32. Discordant contact relationships. Zones of high sulphide, coarse grained fe-mg carbonates (fmc), coarser

sericite (s) and quartz (q) show a discordant contact relationship to the much finer grained quartz – sericite zones,

upper right field, which forms the matrix of the primary felsic ash tuffs. Transmitted cross polarized light, 25x.

53

a

b

Plate 33. Gold and sulphide grain relationships. Gold (au) grains are in stable contact with sphalerite (sp) and

chalcopyrite (cp). Scattered euhedral, generally inclusion free pyrite (py) grains are scattered throughout the matrix

and form internally to both chalcopyrite and sphalerite. On plate 32a, gold grains are also spatially related to early

quartz. On plate 32b, gold grains are entirely embayed within larger sphalerite grains and have no association with

silicate gangue minerals. Reflected light, 50x.

54

a

b

Plate 34. Sulphide – silicate relationships. Bands of sphalerite (sp) pyrite (py) and lesser chalcopyrite (cp) form

semi massive sulphide bands, plate 34a. Sulphide grains are associated with a fe-mg carbonate and medium to blue

green chlorite as the principle gangue minerals. Plate 34a, reflected plane polarized light 25x; plate 34b, transmitted

cross polarized light 25x. Identical fields of view in both plates.

55


a

b

Plate 35. Macroscale images sample 13 – 27 @ 72.35m. The quality of these images are degraded as no prepared

off-cut block was used in the construction of the images. The photographs have been taken from the rough reject

blocks. The rough off-cut block, plate 35a, is 55 mm long, the detailed macroscale image; plate 35b has a field of

view of 12 mm and a magnification of 40x.

56

Protolith – Rock Name: Dioritic Sub-volcanic intrusion.

Alteration Assemblage: calcite-sericite +/- chlorite


significantly plagioclase phyric, pale greenish grey rock. The matrix of the sample has been

extensively overprinted and blurred by moderately texturally destructive calcite. Relevant

textural and morphological characteristics include:

Greater than 60% of the sample is composed of crowded medium grained plagioclase

phenocrysts which are set off against a muddy green grey matrix.

The sample exhibits no evidence of internal stratification.

There is no definitive macroscale evidence for the development of an interlocked

crystalline matrix.

Discrete quartz grains are not identified within the rock matrix.

Disseminated pyrite grains, with no vein association, and with no other sulphide phases,

are scattered throughout the rock matrix. Pyrite averages approximately 2%.

Very minor chlorite aggregates are visible within the rock matrix.

Very minor scattered leucoxene grains are likely present within the sample matrix.


Primary Mineralogy


Quartz 0.5 – 0.75% 0.1 – 0.2 mm

Plagioclase 20 - 24% (60-65%) 0.2 – 1.5 mm



Calcite 25 – 30% 0.1 – 0.5 mm

Sericite 18 - 20% < 0.1 – 0.2 mm

Chlorite 19 - 23% < 0.2 mm

Rutile 0.35 – 0.55% < 0.1 mm

Pyrite 1.5 – 2.0% < 0.1 – 0.45 mm

Hematite 0.5 – 0.75% < 0.1 mm


Sphalerite trace < 0.05 mm



):0.082



Quartz: Primary quartz grains in this sample occur as well rounded, grains or quartz eyes, which

lack any evidence for polysutured grain boundaries. Quartz is typically not identified as free

quartz within the sample matrix.

57

Plagioclase: The bulk of the sample is composed of abundant, euhedral plagioclase grains. Most

of these grains have been extensively overprinted by sericite and calcite. When present albite

twin plane orientations have An contents which are estimated at An60 – 70.


Calcite: Calcite grains have significantly replaced many of the primary plagioclase grains noted

within the sample matrix. These grains are forming extensive overgrowths on plagioclase grains

and are forming irregular clots and aggregates within the matrix. Evidence for dolomitic or

ankeritic rhombs is very limited and most of these grains are Ca carbonates.

Sericite: Sericite occurs as very fine grained replacements of plagioclase phenocrysts and as

persistent very fine grained non-aligned aggregates within the sample matrix.

Chlorite: Chlorite has a similar distribution to sericite and this mineral is commonly identified

forming between the interstitial spaces of plagioclase grains. Chlorite has a medium green

coloration and is likely an Mg chlorite.

Rutile: Lathe like rutile aggregates are noted throughout the sample matrix. These grains

occasionally form the outlines or borders to leucoxene shaped mineral grains.

Pyrite: Euhedral pyrite grains are noted as uniform disseminations throughout the sample matrix.

Most of these grains have no vein association and although some grains may have inclusions

most grains lack significant inclusions.

Chalcopyrite: Chalcopyrite occurs as very small inclusions within the larger pyrite grains.

Chalcopyrite has not been identified in any other resident sites.

Sphalerite: Sphalerite, like chalcopyrite, is only identified at trace levels as very minor and small

inclusions within sphalerite grains.

Structural Characteristics: In contrast to other samples in this suite, this sample lacks a well-

developed penetrative fabric. The sample has no significant internal discontinuities.

58

a

b

Plate 36. Matrix textural characteristics. Under plane polarized light, plate 36a, the euhedral nature of matrix is

clearly noted. Matrix plagioclase (p) grains form small button shaped aggregates. A coarse chlorite (c) clot is noted

(plate 36a,b) and large plagioclase phenocrysts are extensively corroded by calcite and sericite. A few opaque pyrite

(py) grains are noted (plate 36b). Plate 36a, transmitted plane polarized light, 25x; plate 36b, transmitted cross

polarized light, 25x. Identical fields of view in both plates.

59

Sample Number: 13 – 29 @20.7m .

a

b

Plate 37. Macroscale images, sample 13 – 29 @20.8 m. The sample has been cut from a fine grained non-

porphyritic flow unit. The sample length shown on plate 37a is 40 mm. The detailed macroscale image has a field of

view of 15 mm and has been taken at a magnification of 30x, plate 37b.

60

Protolith – Rock Name: Chloritized Intermediate Flow.

Alteration Assemblage: chlorite-sericite-epidote

Macroscale Textural and Morphological Characteristics: This fine grained, dark green

samples has the following macroscale textural and morphological characteristics:

The sample contains a significant percentage of mm scale greenish black chloritic

aggregates. These aggregates have sub-rounded edges and appear to be forming as

secondary matrix replacements.

Pyrite is identified as a single cm scale cluster or amalgamation of numerous smaller

grains. There is no evidence that these grains are forming in as early compositional

lamella or that they have a discordant vein relationship.

The matrix of the sample contains a low level, 2 – 3% of fine grained calcium or fe-mg

carbonates.

The sample contains sporadic very well rounded, secondary (?) quartz grains. Some of

these are 4 – 6 mm across.

No primary phenocryst grains are preserved in this sample.


Primary Mineralogy


Quartz 6 - 7% 0.1 – 0.3 mm

Plagioclase 10 – 13% (45 – 50%) < 0.15 mm



Chlorite 30 - 33% 0.1 – 0.5 mm

Sericite 25 – 28% 0.15 – 0.6 mm

Epidote 15 - 17% < 0.15 mm

Calcite <0.2% < 0.2 mm

Quartz: 1.0 – 1.5% < 0.2 mm

Pyrite 0.75 – 1.0% < 0.05 – 0.4 mm



Hematite 0.25% < 0.15 mm

(bracketed numbers indicate pre-alteration mineral percentages)



): 0.056



Quartz: Primary quartz grains occur as small disseminations throughout the matrix of the

sample. These grains have polysutured and recrystallized interiors and are locally overprinted

along their margins by felted masses of sericite and chlorite.

61

Plagioclase: Most of plagioclase in this sample has been extensively overprinted and corroded

by fine grained sericite or chlorite. Occasionally these grains have well preserved albite twin

planes which suggest that they have an An content of approximately An60.


Chlorite: Chlorite occurs in two principle forms:

As irregular amorphous vein or alteration fronts which anastomose and cut discordantly

throughout the sample. These appear to represent alteration fronts which may have an

narrow sub-mm scale epidote rind.

Pseudo-morphing rectangular crystal forms, either plagioclase or an unidentified mineral,

which completely overprint primary mafic mineral phase.

These grains are always non-aligned to the dominant penetrative fabric recorded in these

samples.

Sericite: Sericite occurs throughout the matrix of the sample as very small grains which have

extensively replaced and overprinted primary plagioclase grains. The vast majority of the sericite

in this sample occurs as very small, felted matrix replacements.

Epidote: In this sample epidote is an important alteration mineral. It is present as well formed,

but small euhedral grains and compositionally varies from zoisite to clinozoisite. These grains

have a strong spatial relationship with epidote and are commonly embedded within chlorite

clusters or form a rind to larger chlorite aggregates.

Calcite: Calcite is rarely identified in this sample it is most commonly documented as very small

isolated aggregates or as vein infill to sub-mm quartz carbonate veins.

Quartz: Secondary quartz is sporadically identified as one of two gangue components, quartz –

calcite, in sub mm, sulphide deficient microveinlets. It is also occasionally noted as isolated

matrix aggregates. Quartz in this sample has no sulphide association.

Pyrite: Pyrite grains are best developed in areas of enhanced secondary chlorite. These grains

locally contain small sulphide or silicate inclusions. Most of the pyrite in this sample is highly

euhedral, lack a vein association, and other than minor sulphide inclusions are not associated

with other sulphide phases.

Chalcopyrite-pyrrhotite: These sulphides are documented only at trace levels are all are found as

small < 50 micron inclusions in pyrite grains.

62

Hematite: Very small, < 100 micron, hematite grains are scattered throughout the matrix. These

grains may have been forming after primary magnetite but no magnetite grains are preserved in

this sample.

Structural Characteristics: This sample has an weak penetrative fabric which appears to have

been extensively overprinted by matrix sericite or chlorite.

Plate 38. Pyrite grain styles. The sample contains very weakly developed disseminated pyrite grains. These grains

have sporadic sulphide and silicate inclusions. The higher relief background lathes or rectangular non-reflective

grains in the matrix of the sample are secondary chlorite grains which may be associated with secondary pyrite

grains. Reflected light, 50x.

63

a

b

Plate 39. Matrix characteristics. The sample contains a few scattered quartz (q) grains. These grains are embayed

in a fine grained strongly sericite (s) and chlorite (c) altered matrix. Secondary chlorite plus or minus epidote forms

an irregular non-planar band across the centre of the field of view. Plate 39a, transmitted plane polarized light, 25x;

plate 39b, transmitted cross polarized light, 25x. Identical fields of view on both plates.

64

Sample Number: 13 – 14@ 318.6

a

b

Plate 40. Macroscale images sample 13 – 14 @ 318.6 m. The macroscale image on plate 40a has a length of 40

mm; plate 40b. The detailed macroscale image has a field of view of 15 mm, at a magnification of 30x.

65

Protolith – Rock Name: Chloritized Intermediate/Felsic Flow

Alteration Assemblage: chlorite-epidote-sericite+/- quartz-sulphide

Macroscale Textural and Morphological Characteristics: This sample has undergone

extensive alteration by both silicate and sulphide assemblages. Because of the intensity of

secondary rock alteration, protolith recognition is challenging. Relevant macroscale features

include:

The sample matrix contains abundant felted, dark green matrix chlorite.

Small euhedral pale cream colored semi-translucent crystals may be zoisite.

Large, cm scale aggregates of pyrite are formed throughout the matrix. These grains are

often flanked or rimmed by small chalcopyrite grains.

Pyrite – chalcopyrite grains contains minor amounts of quartz, chlorite and calcite as the

principle gangue mineral assemblages.

Small euhedral quartz grains are identified in this significantly altered rock unit and

appear to be the sole recognizable primary mineral grain.

The rock matrix contains 5 – 6%, calcite. Most of this is concentrated within the coarse

pyrite –chalcopyrite aggregates.

The sample lacks a penetrative fabric and contains no significant discontinuities.


Primary Mineralogy


Quartz 9 - 12% < 0.1 – 0.8 mm



Chlorite 21 – 26% < 0.1 – 0.4 mm

Sericite 19 – 23% < 0.15 mm

Epidote 15 – 17% 0.1 – 0.3 mm

Quartz 3 - 5% 0.1 – 1.2 mm

Calcite 2.5 – 4.0% 0.1 – 1.5 mm

Pyrite 8 – 10% 0.2 – 4.0 mm

Chalcopyrite 2.5 – 3.5% 0.1 – 2.25 mm

Magnetite trace < 0.05 - 0.1 mm


Gold 6 grains < 5 – 20 microns



): 0.214



Quartz: Quartz is the sole remaining primary mineral grain in this sample. Quartz is identified

either as:

Euhedral, primary mineral grains lacking polysutured interiors and present as the primary

phenocryst phase.

66

Primary quartz grains are present as very small matrix grains.

Secondary Mineral Grains

Chlorite: Chlorite is identified in three resident sites including:

Chlorite grains occur throughout the matrix as felted mineral aggregates.

Chlorite occurs as a significant gangue mineral in chlorite-epidote plus or minus quartz

sulphide veinlets.

Chlorite flanks and forms a halo to sulphide grain aggregates.

Sericite: In this sample significantly enhanced very fine grained sericite outlines rectangular

crystal grains which were originally plagioclase. Sericite is also identified as very fine grained

matrix replacements.

Epidote: Epidote forms small disseminated aggregates which closely tracks and follows the

distribution of secondary chlorite. Both zoisite and clinozoisite are identified in this sample with

both minerals forming stable contact relationships.

Quartz: Secondary quartz is often identified as small pits or inclusions to large sulphide grains,

or a as a lesser component to carbonate-chlorite-epidote veinlets.

Calcite: Calcite grains have two very specific resident sites including:

Forming in close spatial association with large sulphide aggregates.

As a significant component to quartz-carbonate-epidote-chlorite veinlets.

Pyrite: Pyrite occurs as large irregularly shaped grains which are commonly inclusion rich and

contain small sulphide (chalcopyrite, pyrrhotite) and oxide (magnetite) and silicate inclusions.

Chalcopyrite: Chalcopyrite grains are forming an envelope to the larger pyrite grains.

Chalocopyrite grains are intimately associated with both epidote and chlorite as the dominant

gangue minerals. Chalcopyrite grains contain silicate inclusions but typically lack oxide or

sulphide inclusions.

Pyrrhotite: Small pyrrhotite aggregates are found as inclusions within large pyrite grains.

Pyrrhotite gains are typically less than 100 microns and present at trace levels.

Magnetite: Magnetite grains are identified as small, but locally euhedral inclusions, within pyrite

grains. There is a weak possibility that these grains are in fact very iron rich sphalerite and non-

translucent, sphalerite grains.

67

Gold: Gold is identified in this thin section but all grains are very small. Many of these grains

are in the 5 micron range with the largest grain being approximately 20 microns. In all cases,

individual gold grains are associated with fine grained white micas, plus or minus silica (?). Gold

grains internal to chalcopyrite was not identified. Weak discoloration and locally changes in the

surface textures of chalcopyrite grains may suggest that gold may be residing in solid solution

with copper, e.g. kostovite (CuAuTe4) ; Auricupride AuCu3).

Structural Characteristics: Quartz is forming non-rotational pressure shadows to large pyrite

grains within this sample. Generally penetrative fabrics are weakly developed. Most of the

chlorite grains have not been reset or aligned to any regional metamorphic planar fabric.

68

a

b

Plate 41. Gold grains and sulphide stability. The sample contains very fine grained gold grains. These grains are

associated with either fine grained micas, plate 41a or are associated with secondary quartz forming in the

interstitium between chalcopyrite grains. Plate 41a reflected plane polarized light 100x, plate 41b, reflected plane

polarized light, 400x.

69

a

b

Plate 42. Sulphide – gangue relationships. A zone of enhanced chlorite (c), epidote (e) and quartz (q) are strongly

associated with coarse chalcopyrite (cp) and pyrite (py) mineral grains. Fine grained, primary sericite (s) grains are

noted throughout the lower third of the field and suggest that the original rock had very high plagioclase contents.

Plate 42a, transmitted cross polarized light, 25x; plate 42b, reflected light, 25x.

70

a

b

Plate 43. Generalized matrix – overprinted protolith textural characteristics. On these images, the fine grained

blue-grey matrix aggregates are primary quartz (q) grains. The mottled yellowish areas are fine grained sericite (s)

which are overprinting early plagioclase grains. Secondary chlorite (c) and quartz form sub-planar alteration fronts

and chlorite-epidote (ce) aggregates are also noted. Transmitted cross polarized light, 25x.

71

a

b

Plate 44. Sulphide – gangue relationships. In these images large pyrite (py) grains are flanked by well-defined

calcite (cc) aggregates and by chlorite (c). Chalcopyrite (cp) grains flank pyrite and are strongly associated with

masses of fine grained epidote (e) and chlorite. The protolith is now recognized only by fine grained sericite (s)

lathes in the upper third field of view. Plate 44a, transmitted cross polarized light, 25x; plate 44b, reflected light,

25x. Identical fields of view both plates.

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