Download Properties of Minerals

Properties of Minerals
Luster
• Appearance of a fresh mineral surface in
reflected light
1. Metallic Luster
4. Pearly Luster
2. Vitreous
Luster- glassy
luster
5. Silky luster
3. Resinous Luster
1.
2.
3.
4.
5.
Pyrite
Quartz
Orpiment
Muscovite
Satin Spar Gypsum
Color
• The wavelength of light that is reflected off of
a freshly broken surface of a mineral.
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Clear
Red
Orange
Yellow
Blue
Green
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Indigo
Violet
Brown
Black
White
Hardness
• A mineral’s resistance to abrasion (being
scraped)
– Mohs scale of hardness
Cleavage
• The tendency of minerals to break along
definite planes of weakness that exist in the
internal structure of the mineral
Gypsum
Fracture
• How a mineral breaks
ConchoidalFracture- surface is
smooth and has
concentric ridges
Obsidian
FibrousBreaks into long
filaments
Asbestos
Streak
• The color of the powder of a mineral after is
has been scraped across a hardened ceramic
surface
Specific Gravity
• Ratio of a minerals weight to the weight of an
equivalent volume of water. Higher Specific
Gravity= Higher Density
Diaphaneity
• The ability of a thin slice of mineral to transmit
light
Transparent- allows most
light to pass through
undistorted
Calcite
Translucent- light
passes through but is
bent and you cannot
resolve images
Muscovite
Opaque- no light
passes through even
the thinnest slice
Cinnabar
Crystal Form
• The assemblage of faces that reflect the
internal molecular structure of the mineral
Magnetism
• Is the mineral attracted to a magnet?
• Magnetite is the most common mineral that
will do this.
Hematite
Double Refraction
• Images appear doubled when viewed through
the mineral specimen- Calcite
Taste
• Most minerals will not have this property.
Never taste a sample unless directed to do so.
Halite
Odor
• A characteristic smell from a mineral- Kaolinite
smells musty or dank when moistened.
Feel
• Surface texture of a mineral. Greasy, slick,
smooth, rough, soapy, veined
Graphite- Greasy
Chemical Reaction
HCl acid on
Calcite