| Diamond |
A scattering of round-brilliant cut diamonds shows off the many reflecting facets.
|
| General |
| Category |
Native Minerals |
| Chemical formula |
C (allotrope of carbon) |
| Identification |
| Molecular Weight |
12.01 u |
| Color |
Typically yellow, brown or gray to colorless. Less often in blue,
green, black, translucent white, pink, violet, orange, purple and red.[1] |
| Crystal habit |
Octahedral |
| Crystal system |
Isometric-Hexoctahedral (Cubic) |
| Cleavage |
111 (perfect in four directions) |
| Fracture |
Conchoidal - step like |
| Mohs Scale hardness |
10[1] |
| Luster |
Adamantine[1] |
| Polish luster |
Adamantine[1] |
| Refractive index |
2.4175–2.4178 |
| Optical Properties |
Singly Refractive[1] |
| Birefringence |
none[1] |
| Dispersion |
.044[1] |
| Pleochroism |
none[1] |
| Ultraviolet fluorescence |
colorless to yellowish stones - inert to strong in long wave, and typically blue. Weaker in short wave.[1] |
| Absorption spectra |
In pale yellow stones a 415.5 nm line is typical. Irradiated and
annealed diamonds often show a line around 594 nm when cooled to low
temperatures.[1] |
| Streak |
White |
| Specific gravity |
3.52 (+/- .01)[1] |
| Density |
3.5-3.53 |
| Diaphaneity |
Transparent to subtransparent to translucent |
| Thermal conductivity |
900 – 2320 W/m K |
| Melting point |
3820 K (3547 °C / 6420 °F) |
| Boiling point |
5100 K (4827 °C / 8720 °F) |
| Solubility |
Resistant to acids, but melts in hot steel |
| Major varieties |
| Ballas |
Spherical, radial structure, cryptocrystalline, opaque black |
| Bort |
Poorly-formed, cryptocrystalline, shapeless, translucent |
| Carbonado |
Massive, microcrystalline, opaque black |
Chemistry Quick Facts
