Crystal system
:                 Orthorhombic                                   Hardness:            8,5
Density:                               3,5 – 3,84                                             Streak:                  White
Colour:                                 Various shades of green, yellow, brownish to green black (can be raspberry-red under incandescent light when chromium is present)
Cleavage:                            Distinct, imperfect
Occurrence:                      ...

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