Sectile - Curved shavings or scrapings produced by a knife blade, (e.g. graphite).
Habit:
Tabular - Form dimensions are thin in one direction.
Hardness:
5.5-6 - Knife Blade-Orthoclase
Luster:
Vitreous (Glassy)
Streak:
white
Optical Properties of Manganokukisvumite
Gladstone-Dale:
CI meas= 0.031 (Excellent) - where the CI = (1-KPDmeas/KC) CI calc= 0.038 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2538,KPDmeas= 0.2556,KC= 0.2638 Ncalc = 1.75 - 1.76