do we need to know the formulas?
| Olivine | |
|---|
| Color | Olive green |
| Streak | White |
| Hardness | 6.5 -> 7 |
| Fracture | |
| Luster | Viteous |
| Habit | Granular, sugary |
| Misc | Translucent, often called durite |
| Pyroxene group | |
|---|
| Color | Black, brown, green, white, violet-brown |
| Streak | White to grey |
| Hardness | 5 -> 6.5 |
| Clevage | 2 planes @ 90 degrees |
| Luster | Vitreous, resinous, dull |
| Habit | Stubby, prismatic |
| Misc | |
| Hornblende | |
|---|
| Color | Black, dark green, brown |
| Streak | White, light grey, colorless |
| Hardness | 5 -> 6 |
| Clevage | 2 planes @ 60 and 120 degrees |
| Luster | Vitreous to dull |
| Habit | |
| Misc | |
| Calcite | |
|---|
| Color | Various |
| Streak | White |
| Hardness | 3 |
| Clevage | 3 planes not at 90* |
| Luster | Vitreous to pearly |
| Habit | Prismatic, Rhombodedral |
| Misc | |
| Plagioclase | |
|---|
| Color | Various |
| Streak | White |
| Hardness | 6 -> 6.5 |
| Clevage | Prismatic; 2 planes @ 90* |
| Luster | Vitreous to pearly |
| Habit | Blocky, prismatic, and tabular |
| Misc | |
| Alkali Feldspar | |
|---|
| Color | Salmon, white, green, blue |
| Streak | White |
| Hardness | 6 |
| Clevage | 2 planes @ 90* |
| Luster | Vitreous to pearly |
| Habit | Blocky, prismatic, and tabular |
| Misc | Has exsolution lamella |
| Garnet | |
|---|
| Color | Varous, but red is common |
| Streak | White |
| Hardness | 5 -> 7.5 |
| Fracture | Conchoidal |
| Luster | Adamantine, greasy, vitreous |
| Habit | Rhombic dodecahedron, cubic |
| Misc | Forms cube or dodecahdral crystals |
| Gypsum | |
|---|
| Color | White to gray |
| Streak | White |
| Hardness | 2 |
| Clevage | 2 planes @ 66 and 114 degrees |
| Luster | Vitreous to silky |
| Habit | Massive, flat, prismatic crystals |
| Misc | Appears fibrous |
| Halite | |
|---|
| Color | White |
| Streak | White |
| Hardness | 2.5 |
| Clevage | Cubric, 3 planes at 90* |
| Luster | Vitreous |
| Habit | Cubic |
| Misc | Tastes salty |
| Hematite | |
|---|
| Color | Red to brown to black |
| Streak | Reddish brown |
| Hardness | 5.5 -> 6.5 |
| Fracture | Conchoidal |
| Luster | Metallic to earthy |
| Habit | Boyryoidal, prismatic, platy, tabular |
| Misc | May be magnetic |
| Magnetite | |
|---|
| Color | Black, gray |
| Streak | Black |
| Hardness | 5 -> 6.5 |
| Fracture | Conchoidal |
| Luster | Metallic to submetallic |
| Habit | Octahedral |
| Misc | ? |
| Muscovite | |
|---|
| Color | White, grey |
| Streak | White |
| Hardness | 2 & 4 (directional) |
| Clevage | Basal, 1 plane at 180* |
| Luster | Vitreous, pearly |
| Habit | Massive, tabular, platy books |
| Misc | Can be peeled off in sheets |
| Biotite | |
|---|
| Color | Dark brown, greenish brown, blackisn brown |
| Streak | White to ggrey |
| Hardness | 2 & 4 (directional) |
| Clevage | Basal, 1 plane at 180* |
| Luster | Vitreous, pearly |
| Habit | Massive, tabular, platy books |
| Misc | Can be peeled off in sheets |
| Pyrite | |
|---|
| Color | Brassy, gold |
| Streak | Greenish black |
| Hardness | 6 -> 6.5 |
| Fracture | Conchoidal |
| Luster | |
| Habit | |
| Misc | |
| Galena | |
|---|
| Color | Grey |
| Streak | Lead grey |
| Hardness | 2.5 -> 3 |
| Clevage | Cubic |
| Luster | Metallic |
| Habit | Cubic |
| Misc | Breaks off into cubes |
| Quartz | |
|---|
| Color | Transparent, various |
| Streak | White |
| Hardness | 7 |
| Fracture | |
| Luster | Vitreous to greasy |
| Habit | Prismatic |
| Misc | Forms 6-sided prisms |
Mineral: naturally occuring inorganic solid with crystlline structure.
Rock: naturally occuring aggregate of minerals or other solid material.
Minerals are classified by their dominant anion.
| Class of mineral | Description | Examples |
|---|
| Silicates | Most abundant minerals in the Earth’s crust and mantle. Composed of silicon and oxygen | ex |
| Carbonates | Major components of limestone and marble | Calcite, Aragonite, Dolomite |
Oxides
Sulfides
Sulfates
Native elements | Gold, silver, copper |
Gems
Gemsones are minerals with special value
Gems are a cut and polished stone created for jewelry
Igneous Rocks
A rock is a naturally occuring consolidated mixture of one or more minerals.
Some rocks are not formed of mienrals. Ex: Coal
The appernce of a rock is detemrined by:
- Mineralogy, the porportions of
The texture of a rock is determined by the size, shape, and arragement of the mineral crystlals.
Igneous rocks are formed by the solidification of a melt (magma or lava)
AAAAA
extrusive = explosive