Mineral necessarily constant for all sides, which is a function of its structure; crystallographic weakness renders some directions softer than others. An example of this property exists in kyanite, which has a Mohs hardness of 5½ parallel to [001] but 7 parallel to [100]. The most common scale of measurement is the ordinal Mohs hardness scale. Defined by ten indicators, a mineral with a higher index scratches those below it. The scale ranges from talc, a phyllosilicate, to diamond, a carbon polymorph that is the hardest natural material. The scale is provided below: Lustre indicates how light reflects from the mineral's
Bityite immersion method are "α = 1.650", "β = 1.658", "γ = 1.660" with 2V calculation of 52.9°. Bityite’s specific gravity is 3.14, and it has a hardness of 4−4.5 based on Mohs scale of hardness. Bityite’s luster is vitreous and pearly on cleavages, and it has a perfect micaceous cleavage on the {001} miller index. Bityite’s crystal habit can display thin and pseudohexagonal platy crystals. Bityite Bityite is considered a rare mineral, and it is an endmember to the margarite mica sub-group found within the phyllosilicate group. The mineral was first described by Antoine François Alfred Lacroix in 1908, and