Isotopically pure diamond C or 100% C. The isotopes of carbon can be separated in the form of carbon dioxide gas by cascaded chemical exchange reactions with amine carbamate. Such CO can be converted to methane and from there to isotopically pure synthetic diamonds. Isotopically enriched diamonds have been synthesized by application of chemical vapor deposition followed by high pressure. The C isotopically pure, (or in practice 15-fold enrichment of isotopic number, 12 over 13 for carbon) diamond gives a 50% higher thermal conductivity than the already high value of 900-2000 W/(m·K) for a normal diamond, which contains the natural isotopic mixture of
Red diamond 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. The color in red diamonds is assessed according to its hue and saturation. Red diamonds can occur with secondary colors, such as brown-red, orange-red, or purple-red, but red is not a modifying color for any other diamond color. Additionally, red diamonds never appear with a tertiary modifying color, as is the case in other diamond colors. A pure red diamond is ideal but an even rarer find than a red with a secondary color.