When diamonds are not located in a tube "kimberlite", and dug through a hard rock or open pit mine, located in alluvial stream beds.

Diamond-bearing kimberlite is an ultrapotassic, ultramafic, volcanic rocks composed of garnet, olivine, Phlogopite, and pyroxene, with a range of trace minerals. Kimberlite occurs in the Earth's crust in vertical, progressive-stack structures, called chimneys.

The unique chemical and molecular structureCrystalline diamond is what gives this gem its hardness and differentiates it from simple graphite. The name "diamond", which is also known as "intended" derives from the greek Adamas, or "untouchables", "invincible" and "invincible."

A type 2 – A diamond has a hardness value of 167 GPa (± 6) when scratched with a touch ultra hard fullerite, and a hardness value of 231 GPa (± 5) after scratching with a diamond. Material "boron nitride," when in a crystallineform that is structurally similar to diamonds, it is almost as hard as diamond. Carbon nitride, in addition, a hypothetical material present, beta-could also be as hard or harder than diamond.

A diamond is unbelievable hardness was the object of curiosity that goes back to Roman times, where it has been shown to burn in scientific experiments, although the reason for its combustion is not understood today.

Experiments in 18-century has shown that diamondsCarbon was created by the lighting of a diamond of oxygen, with the end product of burning lime, acid gases, or carbon dioxide.

In metallurgy and materials science, the term "resistance" describes the resistance of a material to rupture in the event of stress or impact.

Although diamonds are the hardest, and therefore the most scratch-resistant mineral on Earth, with a rating of 10 Mohs, its "strength" rating is moderate, dueits ability to fracture along cleavage planes. By comparrison, a hardness rating of 9, which means that a diamond is 4 times "difficult" as sapphire, sapphire, sapphire has a rating of excellent toughness. Hematite has a hardness of only 5.5-6.5, but its resistance is rated excellent.