Egypt
联系人 Mr. mohamed
cairo, cairo, cairo
Crystal system
Trigonal
Twinning
Common as simple contact twins
Cleavage
Perfect on {***1}, rhombohedral cleavage
Fracture
Conchoidal
Tenacity Brittle
Mohs scale hardness 3.5 to 4
Luster
Vitreous to pearly
Streak
White
Specific gravity
2.*4–2.*6
Solubility
Poorly soluble in dilute HCl unless powdered.
Other characteristics May fluoresce white to pink under UV;
triboluminescent.
