Brittle - Generally displayed by glasses and most non-metallic minerals.
Habit:
Pulverulent - Forms a loose, poorly-coherent powdery mass.
Habit:
Striated - Parallel lines on crystal surface or cleavage face.
Habit:
Tabular - Form dimensions are thin in one direction.
Hardness:
2.5-3 - Finger Nail-Calcite
Luminescence:
Fluorescent, Short UV=green, Long UV=green.
Streak:
light yellow
Optical Properties of Dewindtite
Gladstone-Dale:
CI meas= -0.155 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.135 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1496,KPDmeas= 0.1523,KC= 0.1318 Ncalc = 1.66 - 1.67
Estimated Radioactivity from Dewindtite - very strong
Specimen Size Weight/Volume (Sphere) *
Calculated Activity Bequerols (Bq)
Calculated Activity Curies (Ci)
Estimated Activity GR(api)
Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.20 cm
88,035,943
2.38E-03
3,568,742.73
1,173.29
100 gm / 3.34 cm
8,803,594
2.38E-04
356,874.27
117.33
10 gm / 1.55 cm
880,359
2.38E-05
35,687.43
11.73
1 gm / 7.20 mm
88,036
2.38E-06
3,568.74
1.17
0.1 gm / 3.34 mm
8,804
2.38E-07
356.87
0.12
0.01 gm / 1.55 mm
880
2.38E-08
35.69
0.01
0.001 gm / 0.72 mm
88
2.38E-09
3.57
0.00
Weight of pure Dewindtite in grams (gm) and Calculated Diameter of a Sphere with a Density of 5.12 gm/cc.*
Goverment Estimate of Average Annual Exposure (
360 mRem)
** Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Dewindtite Classification
Dana Class:
42.09.08.01(42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen
Chemical Formula: 
- very strong