|
INVESTIGATIONS
|
Stone |
RI min |
RI max |
Biref min |
Biref max |
Dens min |
Dens max |
Colour |
Locality |
Info |
nx min |
nx max |
ny min |
ny max |
nz min |
nz max |
Spectrum |
UVS |
UVL |
Reference |
|
Neptunite |
1.69 |
1.73 |
0.04 |
0.04 |
3.19 |
3.19 |
very dark orangy red, almost
black |
|
11.78ct |
|
|
|
|
|
|
|
|
|
Gems & Gemology eBrief 2013
Summer, p118 |
TABLES
|
Stone |
RI min |
RI max |
Biref min |
Biref max |
Dens min |
Dens max |
nx min |
nx
max |
ny min |
ny max |
nz min |
nz max |
Reference |
|
Neptunite |
1.69 |
1.736 |
0.029 |
0.045 |
3.19 |
3.23 |
1.690 |
1.691 |
1.693 |
1.700 |
1.719 |
1.736 |
http://www.geminterest.com
|
|
Neptunite |
1.69 |
1.736 |
0.029 |
0.045 |
3.19 |
3.23 |
|
|
|
|
|
|
http://www.gemmology.be
|
|
Neptunite |
1.69 |
1.736 |
0.029 |
0.045 |
3.19 |
3.23 |
1.690 |
1.691 |
1.693 |
1.700 |
1.719 |
1.736 |
Joel Arem, Color Encyclopedia
of Gemstones, 1987
|
|
Neptunite |
1.69 |
1.736 |
0.029 |
0.045 |
3.19 |
3.23 |
1.690 |
1.691 |
1.693 |
1.700 |
1.719 |
1.736 |
Tables of Gemstone
Identification, Roger Dedeyne, Ivo Quintens, 2007
|
|
Neptunite |
1.69 |
1.736 |
0.029 |
0.045 |
3.19 |
3.23 |
|
|
|
|
|
|
Gemology Tools Professional 2010
|
|
Neptunite |
1.69 |
1.735 |
0.028 |
0.046 |
3.17 |
3.25 |
|
|
|
|
|
|
Gemmo.eu 2013
|
CAUSE OF COLOUR
|
Stone |
Colour |
Cause of
colour |
Reference |
|
Neptunite |
red-orange |
charge transfers
Fe-Ti |
http://minerals.caltech.edu |
MINERAL INCLUSIONS
LOCALITIES
CHEMICAL DATA (%)