Basic Gemmology for All

8/11/2019 Basic Gemmology for All

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Basic gemmology for all.By Dr Jagath Wijesinghe. MBBS. MRCP( UK)

For most upate etai!s p!eae "isit http#$$%%%.rea!natura!gems.&om$

'here are our Cs traitiona!!y use in gem es&ription. 'hey are Co!our C!arityCaret %eight an Cut.

Colour

'here are three main &omponent to es&ri*e &o!our in gem stone they are hue

(they are simp!y &o!ours in rain *o%) saturation an tone or *rightness. When%e es&ri*e &o!our %e nee a!! these &omponents.

Hue:'he essentia! impression o &o!our that %e noti&e immeiate!y (Re B!ue+reen ,e!!o% et&).

'here are -/ name &o!ours a&&oring to 0ationa! Bureau o stanars (US)1&&oring to +21 Co!our es&riptions or Co!our +emstones there are 34 &o!oursor hues es&ri*e *ut there are no p!a&es or pin5 an *ro%n &o!ours.'here are on!y se"en &o!ours in rain*o% %hi&h is o*"ious or untraine eye theyare "io!et inigo green *!ue ye!!o% orange an re (*!a&5 %hite pin5 an

grey are not mention)'raitiona!!y use "arious terms Kashmir *!ue Kashmir area use to prou&e eep*!ue &o!our han!ooms an simi!ar &o!our *!ue sapphire oun in Kashmir %as!egenari!y &a!! Kashmir *!ue sapphire. Corn!o%er *!ue &orn!o%er is a !o%er in6ng!ish &ountrysie sapphire o it s &o!our are oun in Sri 7an5a. Roya! *!ueS%iss *!ue 7onon *!ue s5y *!ue are a!so simi!ar!y use to es&ri*e &o!ours intopa8. Pigeon *!oo most o goo 9ua!ity ru*ies are in the &o!our o pigeon:s*!oo. 'raitiona!!y &o!our o tan8anite grae as 1111 111 11 1 B an C *ythe !o&a! miners an traers in 'an8ania.

,ou &an ha"e gems any mi;ture o these &o!our Spe&trum. Rain*o% &o!our o

gems
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'his is the most esira*!e &orn!o%er *!ue in *!ue sapphire

Tone or brightness:the !ightness or ar5ness o the &o!our.'his te!!s us ho% strong the &o!or is ("ery !o% !o% meium an high). 'one or*rightness is es&ri*e as the re!ati"e !ightness or ar5ness o a 0ame

= >C >Co!our!ess or White4 >6?7 >6;treme!y !ight- >@7 >@ery !ight3 >7 >7ightA >M7 >Meium !ight

>M >Meium >MD >Meium ar5/ >D >Dar5 >@D >@ery ar5 >6?D >6;treme!y ar54= >B7 >B!a&5

Saturation:Purity o the &o!or. +emstones that ha"e rea! ar5 tone or rea!!ight one (%ashe out) ne"er rea&h a high saturation. 'he esire appearan&e isappea!ing an *right an &ou! *e &a!!e E@i"iE.

Saturation es&ri*e ho% pure is the &o!or or Saturation is es&ri*e as thestrength or purity o a


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>" >@i"iFor e;amp!e %hen %e es&ri*e &o!or o tan8anite %e es&ri*e hue as *!uish "io!etor "io!et *!ue epening on preominate &o!or the tone is (meium or M) anthe saturation is ("i"i or @ ) so %e &an es&ri*e the &o!or as *!ue$"io!et $ orB$@ $ or u!! &o!or es&ription

Color change'his is use to e;p!ain the &o!or &hange phenomena o a!e;anrite.Co!or &hange a*i!ity is a resu!t o the presen&e o &hromium ions an the %ay theya*sor* an re!e&t !ight. With spe&trometer a!e;anrite sho% a *an at =nm*et%een re an green.

Day!ight &ontains high proportions o *!ue an green !ight an in&anes&ent!ighting &ontains a higher *a!an&e o re !ight. When the !ight is *a!an&e(ay!ight) the stone is green *ut %hen the !ight sour&e is reish (in&anes&ent)the stone appears re.

'he &!oser the &o!ors are to pure green an re the higher the "a!ue.'ermino!ogy to e;p!ain &o!or &hange4$ as a per&entage> 1!e;anrite &an e;hi*it e"erything rom 4== to just 4 &o!or&hange.-$ e;p!ain the &o!or &hange as Wea5 Meium Meium>Strong Strong @ery>Strong.

Co!our 8oneSome stones sho% &o!ours on!y in parts or !ayers. 'his eature &an *e seen rare!yin natura! an &ommon!y in heat treate gems. When it is "isi*!e to na5e eye it

is &onsiere to *e un%ante ee&t. Co!our 8one &an *e a natura! !ogo as it is not&ommon to see in syntheti& gems.2n our gems %e e;p!ain0one# 'he &o!our ise9ua!!y istri*ute an no &o!our 8ones.@isi*!e %ith 4=? magnii&ation# &o!our8oning &an *e seen on!y %ith magnii&ation@isi*!e %ith magnii&ation &amera!ens# "isi*!e %ith 0i55on 4= mm -. @R !ens.@isi*!e to na5e eye# Stone has&!ear!y "isi*!e &o!our pat&hes or !ayers.

ClarityDeens on ho% many &ra&5s an in&!usions are in gems. Co!our gems are "eryierent rom iamon on!y those "isi*!e to the na5e eye shou! in!uen&e theina! grae. 0atura! in&!usions may in&rease the "a!ue o gems as they are the

%ho!e mar5 an !ogo o the nature %hi&h %i!! not usua!!y in in !a* mae gems.'here are se"era! traitiona! %ay o es&ri*ing it eye &!ean !oop &!eanmi&ros&opy &!ean et&.

Inclusions-they are parti&!es o impurities %ith in the gem stone. 'hey areappearing as ash !i5e !a5es &ra&5s or ra&tures ruti!e as &!ous &rysta!s&ontrasts or other impere&tions'ype# it is *etter to ha"e &rysta! or ruti!e in&!usion than ha"ing &ra&5s or ra&ture


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*e&ause they are natura! !ogo o gemstone.Si8e# Sma!!er in&!usions are !ess istra&ting an thus *etter.0um*er# +enera!!y the e%er the in&!usions the *etter.7o&ation# near the gir!e rather than ire&t!y uner the ta*!e a&et ae&t "a!ue!ess. Simi!ar!y a eather perpeni&u!ar to the ta*!e is !ess !i5e!y to *e seen than

one !ying para!!e! to the ta*!e. 1 &ra&5 near the &u!et or &orner %ou! o*"ious!yin&rease the &han&es o *rea5age more than one %e!! into the gem. Simi!ar!y anopen ra&ture on the &ro%n is more !i5e!y to &hip than one on the pa"i!ion.2n&!usions in &ertain positions may a!so re!e&t ma5ing a sing!e in&!usion "isi*!ethroughout a gem.

+emmo!ogi&a! 2nstitute o 1meri&a &!assiy &!arity as o!!o%s.'here are three major types ('ype 4 type - an type 3)'ype 2 19uamarine Chryso*ery! Citrine 'opa8 Smo5y Guart8 +reen'ourma!ine 'an8anite an B!ue Hir&on.'ype 22 1!e;anrite 1methyst +arnets Periot 2o!ite Ru*y Sapphire Spine!some 'ourma!ine'ype 222 6mera!s Re I Pin5 'ourma!ines.'here are / su* i"isions in ea&h type

+21 C!arity 'ypes or Co!our +emstones

'ype 4+emstones that are norma!!y oun to *e &!ean.@@S >Minute to not ete&ta*!e@S >MinorS24 >0oti&ea*!e to o*"iousS2- >*"ious to prominent24 >Prominent moerate ae&t on appearan&e or ura*i!ity2- >Prominent se"ere ae&t on appearan&e I ura*i!ity23 >Prominent se"ere ae&t on *eauty transparen&y I ura*i!ity

'ype - >+emstones that norma!!y may ha"e a e% in&!usions.@@S >Minor@S >0oti&ea*!e to o*"iousS24 >0oti&ea*!e to o*"iousS2- >*"ious to prominent24 >Prominent moerate ae&t on appearan&e or ura*i!ity2- >Prominent se"ere ae&t on appearan&e I ura*i!ity23 >Prominent se"ere ae&t on *eauty transparen&y I ura*i!ity

'ype 3 >+emstones that norma!!y o not &ome &!ean.@@S >0oti&ea*!e to o*"ious@S >0oti&ea*!e to o*"iousS24 >*"ious to prominentS2- >*"ious to prominent


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24 >Prominent &onsiera*!e ae&t on appearan&e or ura*i!ity2- >Prominent se"ere ae&t on transparen&y or ura*i!ity23 'ype 3 >Prominent se"ere ae&t on *eauty transparen&y I ura*i!ityDe&!ass >Stones not transparent *e&ause o in&!usions

Cart %eight1 &arat e9ua!s 4$ o a gram (or 4$4A- o an oun&e). 6a&h &arat is urther i"ieinto points ea&h point representing 4$4==th o a &arat.4+ram L &arets4==points L 4&aretSma!! gems are oun in many p!a&es *ut *igger gemstones are not that &ommonso automati&a!!y higher the &aret "a!ue the gem is more e;pensi"e an "a!ua*!e.

6.g.4$ Sing!e gem %eight &arets %i!! *e more e;pensi"e than t%o gems %eight o

/&arets in same &o!our an &!arity.

-$Weight tota! stone pri&e4&t 4===-&t 3===3&t /===A&t 4====

Cut

Cutting a raw stone into a faceted and polishedgemstone is a multi-step process. Each step is criticalto the final outcome. The steps are:MaringClea!ingSawing"ough shaping#irdling or rounding$aceting and polishingMaring: % rough stone is mared prior to clea!ing orsawing to determine the direction of the grain or&clea!age&' eliminate waste' and bypass inclusions orimperfections. The natural shape of the rough stonewill also be a ma(or factor in deciding how to cut thestone.


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Clea!ing' rough stone is clea!ed or split along itsgrain' if there are defects or inclusions which wouldpre!ent it from being made into a single gemstone.Sawing' we do not do this unless the customer ass to

do so as it might reduce the end weight. )e manuallyapply to lap to get the ma*imum yield of reco!ery.+ther wise' the rough stone is cut to a shape thatappro*imates the shape of the finished stone butwithout the facets."ough Shaping' manually' stone is applied to rotatinglap to get its predetermined' desired final shape'before fi*ing to dop-stic.

#irdling' the rough is fi*ed in to a stic. The stone isapplied to rotating lap rounding its girdle area in toits predetermined shape.$aceting and polishing' The stic with the stone isfi*ed to faceting gear. The cutting and polishing ofeach facet is accomplished by pressing it against are!ol!ing lap. ,uring this faceting stage the angles ofeach facet must be cut in order to maintain symmetry

and produce ma*imum brilliance. #emmologicalgeometry is !ery important in this stage. )e usedifferent laps during faceting and polishingdepending on the gem material.+oo 9ua!ity &ratsman a!%ays &an impro"e inherent *eauty appearan&e an&!arity.

part of faceted gem

'a*!e#is the !at top sura&e o a &ut gemstone.

Cro%n# reers to the upper ome sura&e a*o"e the gir!e o a &ut stone.

Pa"i!ion#is the tapere uner ha! or *ase o a &ut gemstone *e!o% the gir!e

+ir!e#reers to the ege %here the &ro%n an pa"i!ion o a &ut gem meet6"a!uation o &ut in"o!"es se"era! major a&tors


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Shape %i!! not ae&t to the "a!ue *ut %hat shape you !i5e. eg o"a! roun&ushion shapeCutting sty!e there are some traitiona!!y a&&epte metho.6g. Bri!!iant &ro%n an step pa"i!ion are mar5et stanar or sapphire.Proportions an epth>Fa&ets are esigne to &reate ma;imum *ri!!ian&e. When

the &ro%n height is too !o% or pa"i!ion is too eep it %i!! ae&t to the *ri!!ian&e.'he epth o the gem is the height o a stone i"ie *y its minimum %ith. 'heEiea!E range !ies *et%een = an =. Uner = a stone might *e &a!!esha!!o%. 1 sha!!o% stone %ith a !ight tone %i!! in it ii&u!t to maintainsaturation. "er = is too eep mean %i!! reu&e *ri!!ian&eNBri!!ian&yUsua!!y e;p!ain in iamon inustry. 'his es&ri*es ho% %e!! a iamon re!e&ts%hite !ight. 'his estimates ma;imum o !ight a stone re!e&ts uner a spot!ight.We &an use this term on %e!! proportiona! &ut high!y rera&ti"e gems !i5e 8ir&onan sapphires2n our gems %e use to e;p!ain *ri!!ian&y as Poor (A=) +oo (=) @ery goo(/=) an 6;&e!!ent (=)

Symmetry "er!y thi&5 or thin gir!e Poor &ro%n an pa"i!ion a!ignment*et%een ta*!e an gir!e Wa"y gir!e >&entre &u!et or *ottom Fa&ets o notmeet at a point Misshapen a&ets an Roune a&et jun&tionsPo!ish an Finish eg. Poor po!ish >o*"ious po!ishing mar5s or s&rat&hes.2t ae&ts to the "a!ue *ut &an usua!!y *e &orre&te *y simp!y re>po!ishing.

#em treatment and enhancement.n&e gemstone enter to the %or! mar5et Peop!e &an in&rease their appearan&ean &hara&teristi& *y many methoFa&eting an po!ishing# +emstones rare!y rea&h you in their rough natura! state.Perhaps the most *asi& Eenhan&ementE i you %i!! is the a&eting an po!ishing oa gemstone in orer to enhan&e its *eauty. 'his enhan&ement o &ourse oes notha"e to *e is&!ose *e&ause the gemOs out%ar appearan&e ma5es it o*"iousthat the pro&ess has ta5en p!a&e. n!y "ery e% gems &an *e use %ith out a&etingan po!ishing eg %ater %orn &rysta!.

0one#2ni&ates this parti&u!ar gemstone has re&ei"e no treatment orenhan&ement.


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2ni!!ing#'he intentiona! i!!ing o sura&e &a"ities or ra&tures usua!!y %ith g!assp!asti& or other oreign su*stan&es to impro"e ura*i!ity appearan&e an %eight.

7aser#'he use o a !aser an &hemi&a!s to impro"e &ra&5s an in&!usion in

iamons.

i!ing$Resin 2nusion#'he intentiona! i!!ing o sura&e &a"ities an ra&tures%ith &o!or!ess oi! %a; or resin to impro"e appearan&e.

2rraiation#'he use o ;>ray raiation to a!ter a gemstoneOs &o!or o!!o%e *yheating Pro&ess.

Diusion $ !atti&e iusion $ *e treate or *ery!!ium treate#'he use o&hemi&a!s in &onjun&tion %ith high temperatures to prou&e &o!or. For e;amp!e%hen sapphires are heate %ith *ery!!ium *right ye!!o% or orange sapphire &an*e prou&e rom %ea5 ye!!o% or greenish gems. Some stunning &o!ors ha"e *eenprou&e using this metho. 2t is "ery important se!!ers shou! is&!ose gemstreate %ith this metho.

Wa;ing#'he impregnation o a &o!or!ess %a; parain on gemstones to impro"eappearan&e.

Dou*!ing or trip!ing>(ou*!ets an trip!ets)# 'hese are &om*ination o t%o orthree parts o same 5in or ierent 5in o gems to resem*!e as sing!e stone. Sothe &ro%n %i!! *e part o one stone an the pa"i!ion %i!! *e origina!!y separatestone.

Center>use &o!or treatment.'he treatment is one in t%o steps. First a !ayer oiusion treatment &o!or is app!ie to a pie&e o &o!or!ess rough. 1 se&on pie&e isthen use to the &o!ore pie&e using high temperature an high pressure. 'his!ea"es the &o!or !ayer on the gir!e p!ane. 'he en resu!t is a sing!e stone %ithe;traorinary &o!or.

For etai!s p!ease "isithttp#$$%%%.rea!natura!gems.&om$

SYNTHETIC GEMSTONES
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A synthetic gemstone is identical to a natural gemstone in almost every way. This includes thesame basic crystal structure, refractive index, specific gravity, chemical composition, colors, andother characteristics. Since the same gemological tests are used for stone identification on bothnatural and synthetic gems, it is sometimes even possible for a gemologist to be puzzled as towhether or not a stone is natural or synthetic. When this occurs, the best course of action is tosend the stone to an accredited gem laboratory, like the emological !nstitute of America. Theycan positively determine whether a stone is synthetic or naturally occuring. "nly minor internalcharacteristics allow separation of a synthetic gemstone from a natural gemstone.

The following gemstones are common synthethics:

Alexandrite

Amethyst

Diamond

Emerald

Opal

Ruby

apphire

pinel

A variety of methods are currently used in the production of synthetic crystals, resulting indifferent #ualities, appearances and prices.

These are:

!rowth from "elt:

The #lame #usion or $erneuil %rocess

%ulling or &'ochrals(i)s Techni*ue Brigman+toc(barger Techni*ue

!rowth from olution:

,ydrothermal "ethod

"elt+diffusion "ethod #lux+transport "ethod

,igh Temperature-%ressure "ethod:

(ull "elting %rocess

&eramic %rocess results in aggregate crystals/


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vs.0"0TAT0O1 !E"TO1E

!mitation gemstones merely imitate the color or look of a natural stone. They can be made out ofanything. A cubic zirconia is an !$!TAT!"% diamond, for example. A blue piece of glass could bean imitation sapphire. A variety of blue synthetic forsterite is an excellent imitation for tanzanite,while chemically, it&s composition is much closer to the yellowish green peridot. Another classicexample is the 'alexandrite' set in many (ewelry pieces is actually a variety of vanadium coloredsynthetic sapphire.

)or further study, ! recommend*

Gems Made by

Man

by

Kurt Nassau

The +hysics and hemistry ofolor, -nd dition

by

Kurt Nassau

Synthetic, !mitation and Treatedemstones

by

Michael O'Donogue

The Mohs Scale of Hardness$ohs Scale was developed in /0/- by erman mineralogist )riedrich $ohs

1/2234/0356

"ohs caleof hardness is a 78AT!9 scale, not proportional. ! mean by this that a mineral withthe hardness of 0 will %"T be twice as hard a a :. 1)or example, diamond is :;< harder thansapphire=6.!t is really a scale of relative 'scratchability'.

23 is softest..................234 is hardest

>/ Talc

>- ypsum

>3 alcite

>: )lourite

>? Apatite

>@ )eldspar

>2 uartz

>0 Topaz
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11/21

>5 orundum

>/; Biamond

#emstones and Mohs Scale

%ot seeing the gem you are looking forC lick Dere=

Biamond* ............./; Syth. $oissanite*.......5.? orundum* ................5

ubic Eirconia*.. .0.? Spinel* ........................0 Topaz* .......................0

merald* .......2.? 4 0 Almandite* ...............2.? 7hodolite* ..........2 4 2.?

+yrope* ........2 4 2.? Spessartite* ...........2 4 2.? Tourmaline* ........2 4 2.?

!olite* ...........2 4 2.? uartz roup* .............2 +eridot* ..............@.? 4 2

Fadeite*.. ...@.? 4 2 Andradite* .............@.? 4 2 Scapolite* ..............@.?

Eircon 1low6* .......@.? Tanzanite* ............@.? 4 2 )eldspars* ............@ 4 2

%ephrite*.......@ 4 @.? "pal* ........................?.? 8azulite* ...............? 4 @

8apiz 8azuli*.....?4 @ Tur#uoise* ..............? 4 @ Sphene* .............? 4 ?.?

Apatite* ...............? 7hodochrosite* ............: oral .....................3 4 :

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Single Crystals - Superconductors

Back to Sapphire

FABRICATION

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cal Properties

al Structure LatticeConst.a

LatticeConst.c

Density(g/cm3)

MeltingPoint C

ThermalExpansionCoefficient10-6

DielectricConstant

LossTangent@10GHz

Hex 4.758 12.991 3.97 2030 7.50 9.3

Cubic 4.216 3.58 2800 12.8 9.8 9x10-3

O4 Cubic 8.083 3.60 2130 7.45

Hex 3.252 5.213 5.605 1975 2.90

3 Cubic 3.905 5.12 2080 10.3 300 2x10-2
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18/21

3 Rhom 3.790 13.11 6.51 2180 9.2 24.5

O3 Ortho 5.43 7.71 7.57 1600 4.50 20 3x10-3

O3 Tetrag 3.756 12.63 1348 4.65 16.8 6x10-4

O3 Tetrag 3.84 12.68 1238 6.00 300

3 Ortho 5.176 5.815 6.1 1870 5.59 16-20 10x10-4

Cubic 5.41 5.8 2500 10.3 27

and Orientations Availablese each crystal is unique, maximum sizes and orientations available will vary. Please contact us for crystals for your specific

ments.

cationsconductor thin films

omeM Site map "ur Ney +ersonnelM ducation +rogrammeM7esearchM +ublications O +roducts

Boo(:Laboratory-grown Diamonds by Jranko Bel(anin, D! 7esearch,and Busan Simic, D! !ndia 1-;;2 Second dition, published by D!6.

+rice* !nd. 7s. 0;;G4

uarterly 1ewsletter:8atest news on trade events, identification ofgems and new developments in research from D! labs in %orth Americaand !ndia.

Educational its on Treated and ynthetic Diamonds:Set of one tosix synthetic, D+DT treated or irradiated diamonds, light to vivid coloursaturation and S! to ! clarity. These kits come with description andidentification cards for each laser4inscribed stone.
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19/21

Rough Diamond !rading and Ealution + 9 Days0nstructors: E?E1A DE?FA101, $.Sc. )A, !ndependent onsultant to D!

BRA1O DE?FA101, J.Sc., )A, BI, +ro(ect $anager, D! 7esearch

eology and the "rigin of Biamonds+hysical and "ptical +roperties of Biamonds

Study of Biamond rystallography and $orphology

Typing of Biamonds

9arious Bistortions "f BiamondPs Shape. Dow to Adopt Shapes.

?ab: +ractical Studies of Biamond Stress and Typing

?ab: +ractical Studies of Weight stimation

Surface )eatures of Biamonds

utting of Biamonds

Biamond ut for Weight, Biamond ut for Q!dealR+rediction by ield or by fficiencyC

larity and olour rading

?ab: +ractical Studies of Surface )eatures of Biamonds

?ab: +ractical Studies in rading and Sorting

lassification of Biamond

Work with Well Shaped rystals

The Jasic ross4section and Alternative ross4sections

Dow to alculate the )uture BiamondPs Weight

Ipdate on the 8atest Biamond Treatments, !mitations and Synthetics?ab: lassification of Biamonds 7ough

?ab: +ractical Studies with %atural, Treated and Synthetic Biamonds

Typomorphic )eatures of Biamonds of 9arious "rigins

+olished Biamonds* $odern rading Systems and +ricing !nformation

Work with !nclusions

Jasic Bifference between Two 7ough Biamonds rading Approaches* lassificationG+ricelist and through +olished +redictionG+olished

+ricelist

9aluation of Biamonds

?ab: valuation of 7ough and +olished Biamonds

nal Testing A person who successfully passes the final exam will earn a D! ertificate or a 8etter of ompletion if final exam is notassed.

Adanced !emmology Education %rogrammes Offered by !emological ,ead*uarters 0nternationalAdanced !emology + &oloured !emstones 3 Day/


20/21

0nstructor: BRA1O DE?FA101C B.c.C !!C #!AC DG!C %roHect "anagerC !,0 Research andEducation

"orning

ause of olour in emstones

orundum Treatments

Betection of Deat Treatments of Ruby and apphire

apphires from around the World

Deat Treatments with hemical lements

)racture4filled orundum

ffect of Deat Treatments on !nclusions

Ise of Advanced !nstruments in Betection of Treatments and Synthetics

The +rogramme also includes a +ractical8ab with 7uby and Sapphire Samples.

Afternoon

World merald 8ocalities )lux and Dydrothermal Synthetic meralds

Emerald enhancement

!dentification of fracture filled emeralds

uality of Fade

A, J and Treated Fadeite Fade

!dentification of dyed Fade with microscopy

!dentification of polymer impregnated Fade by )T!7 spectroscopy

The +rogramme also includes a +ractical 8ab with merald and Fade Samples.

?aboratory+ !rown Diamonds 3 Day/

0nstructor: BRA1O DE?FA101, J.Sc., BA, )A, BI, D! 7esearch

Topics &oered

$orphology and Source of %atural Biamonds

xternal and internal characteristics of %atural Biamonds

What are hameleon BiamondsC

auses of olour in %atural and 8ab4grown Biamonds

Biamond 1natural and lab4grown6 Types

D+DT 11Digh +ressure Digh Temperature6 Technology of rowing Biamonds

9B 1hemical 9apour Beposition6 Technology of rowing Biamonds

olour Treatments of 8ab4grown Biamonds

Testing and !dentification of 8ab4grown Biamonds 1!System6

Standard emmological $ethods 1microscopy, +), I96

Advanced emmological $ethods 1spectroscopy, chemistry6

+roducers and $arketing of em4#uality 8ab4grown Biamonds

rading and ertification of 8ab4grown Biamonds at D! 8abs


21/21

The +rogramme also includes a +ractical Workshop with 8ab4grown Biamonds.

Treatments of Diamonds 3 Day/

0nstructor: DGA1 0"0&C J.Sc., ), S, $anager, D! !ndia

Topics &oered

&larity "odifications

)racture )illing and Stability

8aser Brilling 1traditional and N$ internal6 and Stability

&olour "odifications

oating 1old and new techni#ue6 and Stability

!rradiation and Stability

Annealing and Stability

Digh +ressure Digh Temperature 1D+DT6 and Stability

ombination Treatments and Stability

Testing and 0dentification ofTreated Diamonds&0 ystem6

Standard emmological $ethods 1microscopy, +), I96

Advanced emmological $ethods 1spectroscopy, chemistry6

!rading and &ertificationof Treated Diamonds at !,0 ?abs

The +rogramme also includes a +ractical Workshop with Treated Biamonds

Basic Gemmology for All

Documents

Transcript of Basic Gemmology for All