Crystal system |
monoclinic (characterized by either a single 2-fold symmetry and/or a single plane of symmetry). |
Habit |
columnar or prismatic, striated and pointed with steep terminations |
Cleavage |
imperfect (or not a smooth or even break) |
Fracture |
uneven. |
Hardness |
6-6.5 |
Specific Gravity |
3.4-3.55 |
Color |
brown or green to dark green. |
Luster |
vitreous and translucent. |
Streak |
pale-brown. |
Distinguishing features |
slender crystals that can poke into the skin and its green/brown color are typical. |
Uses |
of interest to collectors and researchers.
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