Special Mineral Properties • Smells like rotting eggs when
Transcript of Special Mineral Properties • Smells like rotting eggs when
Special Mineral Properties
Unit Essential Question: How can we use the properties of a mineral to identify it?
Presentation Objectives: § Identify and describe unique properties that can make it easy to identify specific minerals.
Special Property 1: Smell and Taste
• Smell - Sulfur and Sphalerite • Smells like rotting eggs when...
• Sulfur is heated. • Sphalerite is sprinkled with
hydrochloric acid (HCl).
• Taste - Halite • Halite is NaCl, which is salt!
Do NOT lick the mineral samples!!
• Some minerals have a distinct smell or taste.
Special Property 2: Radioactivity• Some minerals contain radioactive elements.
• Most common are uranium and thorium.
• Use a Geiger counter to detect the energy released from these elements in the minerals.
Uraninite Thorianite
Special Property 3: Magnetism
• Magnetite is a mineral made out of iron. • It has magnetic properties which means it
attracts magnets or other metal objects.
Magnetite at the Smithsonian
Special Property 4: Double Refraction
• Calcite is a clear mineral. • When light passes through the mineral, it splits
into two and produces a double image.
Halite Calcite
Special Property 5: Reaction with HCl
• Calcite is also easily distinguished from halite because when dilute hydrochloric acid is placed on the mineral it bubbles and fizzes.
• This does not happen with halite. • It can happen with dolomite if powdered first.
Special Property 6: Fluorescence• Some minerals glow when placed under a UV light.
• They absorb the UV light and release it as visible.
Fluorite
Calcite
One More For Fun!• The mineral Ulexite is made from fibers that are
parallel and close together. • They act like fiber optic cables which transmit light
information from one place to another.
• Even though the mineral is translucent, the image from underneath is brought to the surface of the mineral.
Often referred to as the TV Stone!