diamonds

grabcad

Diamond, pronounced as /ˈdaɪəmənd/ or /ˈdaɪmənd/, is a metastable form of carbon with carbon atoms arranged in a diamond lattice, a variation of the face-centered cubic crystal structure. Despite being less stable than graphite, its conversion rate to graphite is negligible under standard conditions. Known for its outstanding physical properties due to strong covalent bonding, diamond exhibits the highest hardness and thermal conductivity among bulk materials, making it valuable in cutting, polishing tools, and scientific applications like diamond knives and anvil cells. Its rigid lattice allows only a few impurities like boron and nitrogen, resulting in colored diamonds such as blue (boron), yellow (nitrogen), brown (lattice defects), green (radiation exposure), purple, pink, orange, or red. Diamond also has high optical dispersion. Most natural diamonds form at depths of 140-190 km in Earth's mantle through minerals, taking billions of years, and are brought to the surface by volcanic eruptions. Synthetic methods like HPHT and CVD can also produce diamond-like materials. Cubic zirconia, silicon carbide, and other simulants resemble diamonds but require gemological techniques for differentiation. The word "diamond" derives from the Greek adámas, meaning "unbreakable."