Red diamonds
| Red Diamond | |
|---|---|
| General | |
| Category | Native minerals |
|
Formula (repeating unit) |
C |
| Strunz classification | 1.CB.10a |
| Crystal system | Cubic |
| Crystal class | Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m) |
| Identification | |
| Formula mass | 12.01 g/mol |
| Color | Fancy |
| Crystal habit | Octahedral |
| Twinning | Spinel law common (yielding "macle") |
| Cleavage | 111 (perfect in four directions) |
| Fracture | Conchoidal (shell-like) |
| Mohs scale hardness | 10 (defining mineral) |
| Luster | Adamantine |
| Diaphaneity | Transparent to subtransparent to translucent |
| Specific gravity | 3.52±0.01 |
| Density | 3.5–3.53 g/cm3 |
| Polish luster | Adamantine |
| Optical properties | Isotropic |
| Refractive index | 2.418 (at 500 nm) |
| Birefringence | None |
| Pleochroism | None |
| Dispersion | 0.044 |
| Melting point | Pressure dependent |
| References | |
Red diamond is a diamond which displays red color throughout its prism, and exhibits all the same mineral properties as colorless diamonds. Red diamonds are commonly known as the most expensive and the rarest diamond color in the world, even more so than pink diamonds or blue diamonds. Red diamonds, just like pink diamonds are greatly debated as to the source of their color, but the gemological community most commonly attributes both colors to gliding atoms in the diamond’s structure as it undergoes enormous pressure during its formation. Red diamonds are among the 12 colors of fancy color diamonds, and are the most expensive price per carat. They will typically run in the hundreds of thousands of dollars per carat range. Since they are the rarest color, it is difficult to find them in large sizes, and they are mostly found in sizes less than 1 carat. Red diamonds only exist with one color intensity, Fancy, although their clarities can range from Flawless to Included, just like white diamonds. The largest and most flawless red diamond is the 5.11 carat Fancy Red Moussaieff Red Diamond, which has internally flawless clarity.
Despite decades of research, scientists are still inconclusive as to the source of red color in diamonds. It is believed that the same cause of the pink color in pink diamonds is the origin of red color as well, but in a more concentrated dose. The most commonly accepted theory is that during the diamond’s formation, a plastic deformation is caused in the crystal lattice structure. Some of the atoms are misplaced as the diamond moves up through its kimberlite deposit, and the intense pressure of this movement causes the varying shades of pink, or red, to appear. This lends credence to the hypothesis that red diamonds are in fact extremely dark pink diamonds, and why only one color intensity is possible. It is possible for red diamonds to be modified by the same secondary colors that can be found modifying pink diamonds as well.
Since red diamonds are classified as diamonds in every sense, they are also graded by the typical four Cs of Connoisseurship: Color, Clarity, Cut and Carat weight. Like with all fancy color diamonds, the Color attribute is considered the absolute most important characteristic of the diamond and is largely what determines its value. The next most important attribute is the diamond’s carat weight, followed by its clarity, and cut.
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Wikipedia