1. Properties of Minerals

2. What is a Mineral? Minerals are formed in nature. Minerals are solids.
Minerals have a crystal
structure and definite chemical composition.
Minerals are inorganic; not
made from a living thing.

3. Color Impurities and other factors can give minerals their color
These minerals are ALL forms of quartz! Color is not a reliable way to describe minerals.

4. Color
Exposure to weather or chemicals may change the color of minerals.
Pyrite turns grey and black.
Oxidation turns iron from
silver to black to red!
Copper turns green!
Color is not a reliable property to use in the identification of minerals!

5. Color Amethyst $68.00 Tanzanite $720.00 Sapphire $500.00 Diamond
$3,000.00
Moissanite
$349.oo
REAL Gold

6. Luster: the way a mineral reflects light
plastic, dull, metallic, waxy, pearly, glassy, silky, earthy
waxy
pearly
metallic
metallic, earthy
dull
glassy, vitreous
resinous, plastic
silky, fibrous

7. Streak
Powder made from rubbing a mineral across a streak plate; sometimes shows a different color than the mineral appears to be.
Shows a mineral’s true color
Galena
Pyrite
Hematite

8. Cleavage
Minerals that break along even lines have cleavage.

9. Types of Cleavage

10. Fracture break along curved or irregular surfaces fibrous
Conchoidal, “shell-shaped”
fibrous
irregular

11. Hardness is the resistance to being scratched
can be measured using a scratch test:
using Mohs Hardness Scale, which compares minerals to each other
using common items such as a fingernail, copper penny, steel knife blade, glass
A fingernail can scratch talc.
Quartz can scratch glass,
but fluorite cannot.

12. Density How much matter there is in a given space
Density = Mass divided by Volume
volume
mass

13. But NEVER taste things in the lab!
Special Properties
Radioactivity
Chemical Reaction
Magnetism
Salty Taste
But NEVER taste things in the lab!
Fluorescence
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