Olivine

(Mg,Fe)2SiO4

Cleavage: [001] Good, [010] Distinct
Color: Yellowish green, Olive green, Greenish black, Reddish brown.
Density: 3.27 - 3.37, Average = 3.32
Diaphaniety: Transparent to translucent
Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Habit: Massive - Granular - Common texture observed in granite and other igneous rock.
Hardness: 6.5-7 - Pyrite-Quartz
Luminescence: Non-fluorescent.
Luster: Vitreous (Glassy)
Streak: white