diamonds properties

Diamond Properties Diamond is the hardest substance known and is given a value of 10 in the Mohs hardness scale, devised by the German mineralogist Friedrich Mohs to indicate relative hardness of substances on a rating scale from 1 to 10. Its hardness, exhibited in its resistance to scratching, is not a constant quantity, but varies in every diamond with the crystallographic direction, being greater on surfaces parallel to the octahedron than on those parallel to the dodecahedron …

…but are frequently useful in identifying the stone and in differentiating between true diamonds and imitations. Because diamonds are excellent conductors of heat, they are cold to the touch. Most diamonds are not good electrical conductors and become charged with positive electricity when rubbed. Another important physical characteristic of the diamond is its resistance to attack by acids or bases. Transparent diamond crystals heated in oxygen burn at about 800° C (about 1470° F), forming carbon dioxide.