|
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 |
columbite-Fe |
|
|
|
|
5,56 |
5,56 |
black |
|
1,046ct |
|
|
|
|
|
|
|
|
|
http://www.dgemg.com/images/PDF-Newsletter/Newsletter2_2023/Columbit.pdf
2023 2 |
TABLES
CAUSE OF
COLOUR
MINERAL
INCLUSIONS
LOCALITIES
CHEMICAL DATA
(%)