Alphabetical
Gemstone List
Click
on a letter for a list of gems:
A| B| C| D| E| F| G| H| I| J| K| L| M| N| O| P| Q| R| S| T|U| V| W| X|Y |Z
Gemstones that begin
with the letter "C"
| Gemstone |
Crystal
System |
Density |
Hardness |
Refractive
index |
Treatments |
Calcareous Concretions
|
aggregate |
2.85 |
2.5-4.0 |
1.530-1.685 |
none known |
Calcite
|
trigonal |
2.70 |
3.0 |
1.486-1.658 |
dying, filling, irradiation |
Cassiterite
|
tetragonal |
6.95 |
6.0-7.0 |
1.997-2.093 |
none known |
Carnelian
|
microcrystalline |
2.65 |
7.0 |
1.535-1.539 |
dying, filling |
Chalcedony
|
microcrystalline |
2.65 |
7.0 |
1.535-1.539 |
dying |
Charoite
|
aggregate |
2.68 |
5.0-6.0 |
1.550-1.559 |
none known |
Chlorastrolite
|
aggreegate |
3.20 |
5.0-6.0 |
1.650-1.660 |
none known |
Chrysoberyl
|
orthorhombic |
3.72 |
8.5 |
1.746-1.755 |
none |
Chrysocolla
|
microcrystalline |
2.00-2.24 |
2-4 |
1.54 |
none |
Chrysoprase |
microcrystalline |
2.65 |
7 |
1.564-1.660 |
dying |
Citrine
|
hexagonal |
2.66 |
7.0 |
1.544-1.553 |
heat |
Copal
|
organic |
1.08 |
2.0 |
1.540 |
heat, heating in oil, dying |
Coral
|
organic |
2.65 |
3.5-4.0 |
1.486-1.658 |
dying |
Corundum
|
trigonal |
4.00 |
9.0 |
1.762-1.770 |
heat,
fracture filling |
Cuprite
|
cubic |
6.14 |
3.5-4.0 |
.2.849 |
none known |
|
