Earthy - Dull, clay-like fractures with no visible crystalline affinities, (e.g. howlite).
Habit:
Massive - Granular - Common texture observed in granite and other igneous rock.
Habit:
Scaly - Morphology like fish scales.
Habit:
Striated - Parallel lines on crystal surface or cleavage face.
Hardness:
2.5-3 - Finger Nail-Calcite
Luminescence:
Non-fluorescent.
Luster:
Adamantine
Magnetism:
Nonmagnetic
Streak:
yellowish orange
Optical Properties of Minium
Dichroism (w):
nearly colorless.
Gladstone-Dale:
CI meas= -0.385 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.272 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1568,KPDmeas= 0.1707,KC= 0.1232 Ncalc = 2.01 - 2.1
Optical Data:
Uniaxial (?), a=2.4.
Calculated Properties of Minium
Electron Density:
Bulk Density (Electron Density)=7.24 gm/cc note: Specific Gravity of Minium =8.93 gm/cc.
Fermion Index:
Fermion Index = 0.2 Boson Index = 0.8
Photoelectric:
PEMinium =1,716.22 barns/electron U=PEMinium x rElectron Density=12428.83 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Minium is Not Radioactive
Chemical Formula: 
