Greigite, a member of the linnaeite group, is extremely rare at MSH. Only a few grains have been recovered.
Color is usually dull black.
Luster is metallic.
Diaphaneity is opaque.
Crystal System is isometric; Fd
Crystal Habits include anhedral crystals to 2mm.
Cleavage none observed.
Fracture is not apparent.
Hardness is 4.
Specific Gravity is approximately 4.0 g/cm
Streak is black.
Associated Minerals include aegirine, analcime, ancylite, calcite,
microcline and rhodochrosite.
Distinguishing Features: Not enough material.
Origin: Named in 1964 after Joseph Wilson Greig (1895-1977),
American petrologist and geochemist.
MinRec 21:313 (1990), Dana 8:101 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE: