| MINERAL (sample #) | DISTINGUISHING PROPERTIES |
| Quartz (3) | No Cleavage (conchoidal fracture); hardness greater than glass; hexagonal crystals; glassy appearance; can be many colors; non-metallic. |
| Plagioclase Feldspar (14) | Harder than glass; 2 cleavages at about 90°; striations on some cleavage surfaces; non-metallic.. |
| Potassium Feldspar (4) | Harder than glass; 2 cleavages at about 90°; striations not present; common in granite and other felsic rocks; pink, white colors common; non-metallic. |
| Hornblende (5) | Black; non-metallic; slightly harder than glass; usually black or dark green; 2 cleavages at 60°/120°; faint gray-green streak; non-metallic. |
| Biotite (2) | Dark black-brown color; softer than glass; 1 perfect cleavage; faint tan-brown streak; non-metallic.. |
| Muscovite (1) | Softer than glass; 1 perfect cleavage; Colorless or silvery appearance;non-metallic; Ke$ha's favorite mineral. |
| Olivine (12) | Harder than glass; green; granular texture; appears to have no cleavage; non-metallic.. |
| Halite (7) | Softer than glass; 3 perfect cleavages at 90° (cubic); Tastes like salt ( it is salt); non-metallic. |
| Calcite (6) | Softer than glass; 3 perfect cleavages not at 90° (rhombohedral shape); non-metallic. |
| Gypsum (13) | Easily scratched with a fingernail; Generally clear to white; one perfect cleavage, may show up to 3 cleavages; non-metallic. |
| Fluorite (11) | Softer than glass; four cleavage planes; high density (heavy); non-metallic. |
| Hematite (10) | Metallic or non-metallic (earthy) luster; strong red-brown streak. |
| Galena (8) | Metallic luster; 3 perfect cleavages at 90° (cubic); high density (heavy). |
| Pyrite (9) | Metallic luster; Hardness than glass; Brassy yellow color, but strong greenish-black streak; crystals commonly cubic; no cleavage. |
Samples:
- 8 -- gneiss
- 9 – schist
- 3 – slate
Igneous samples:
- 5a – granite & 5b – granite pegmatite (v. coarse-grained)
- 14 – rhyolite (porphyritic texture)
- 6 – gabbro (dark color, coarse-grained, plagioclase feldspar)
- 7a – basalt (& 7b – vesicular basalt)
- 12 – obsidian (glassy texture)
- 16 – pumice (frothy texture, low density)
Non-igneous samples with crystalline textures:
- 10 – quartzite (metamorphic)
- 11 – marble (metamorphic)
- 13 – rock gypsum (sedimentary)
- 15 – dolomite (sedimentary)
| Sedimentary | Igneous* | Metamorphic |
| conglomerate (2) (pebbles, clastic) | granite (5a & b) (Felsic, coarse-crystalline) | gneiss (8) (Foliated-crystalline) |
| sandstone (1) (sand, clastic) | gabbro (6) (Mafic, coarse-crystalline) | schist (9) (Foliated-crystalline) |
| shale (17) (silt and clay particles, clastic) | basalt (7a & b) (Mafic, fine-crystalline) | slate (3) (Foliated-crystalline) |
| rock gypsum (13) (gypsum, crystalline) | pumice (16) (Felsic, frothy glass, bubbles) | quartzite (10) (Non-foliated, crystalline) |
| fossiliferous limestone (4) (calcite, fossils, clastic) | obsidian (12) (Felsic, glass) | marble (11) Non-foliated-crystalline) |
| dolomite (15) (powdered reacts with HCl, crystalline) | rhyolite (14) (Felsic, fine or mixed sizes, crystalline) |
*For the igneous rocks: be able to determine whether they are intrusive or extrusive. Also state whether they have a special texture (porphyritic, vesicular, pegmatitic), and be sure to include the texture in the name of the rock.
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