Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)
Hardness:
5.5 - Knife Blade
Luminescence:
Non-fluorescent.
Luster:
Silky
Streak:
greenish black
Optical Properties of Ludwigite
Gladstone-Dale:
CI meas= 0.062 (Fair) - where the CI = (1-KPDmeas/KC) CI calc= 0.037 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2404,KPDmeas= 0.2342,KC= 0.2497 Ncalc = 1.92 - 2
Optical Data:
Biaxial (+), a=1.83-1.85, b=1.83-1.9, g=1.97-2.03, bire=0.1400-0.1800, 2V(Calc)=0-68, 2V(Meas)=Small. Dispersion r >> v extreme.
Pleochroism (x):
dark green.
Pleochroism (y):
dark green.
Pleochroism (z):
dark reddish brown.
RL Anisotrophism:
Strong, yellowish brown to bluish violet gray.
RL Bireflectance:
Pinkish gray to dark greenish gray.
Reflectivity
Standardized Intensity (100%) Reflection Spectra of Ludwigite in Air
λ
R1
R2
∑ R1(λ)
∑ R2(λ)
400 nm
10.10
13.80
420 nm
9.70
13.20
440 nm
9.30
12.60
460 nm
9.00
12.10
480 nm
8.70
11.80
500 nm
8.50
11.50
520 nm
8.20
11.30
540 nm
8.10
11.20
560 nm
7.90
11.00
580 nm
7.80
10.90
600 nm
7.60
10.80
620 nm
7.50
10.80
640 nm
7.40
10.80
660 nm
7.30
10.80
680 nm
7.20
10.80
700 nm
7.20
10.90
Calculated Relative Intensity Colors of Ludwigite in Air
Relative Intensity
0%
100%
200%
300%
400%
500%
600%
700%
800%
900%
1000%
R1
R2
Calculated Properties of Ludwigite
Electron Density:
Bulk Density (Electron Density)=3.65 gm/cc note: Specific Gravity of Ludwigite =3.75 gm/cc.
Fermion Index:
Fermion Index = 0.04 Boson Index = 0.96
Photoelectric:
PELudwigite = 9.17 barns/electron U=PELudwigite x rElectron Density= 33.46 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Ludwigite is Not Radioactive
Chemical Formula: 
