Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. At room temperature and pressure, another solid form of carbon known as graphite is the chemically stable form of carbon, but diamond almost never converts to it. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are utilized in major industrial applications, such as cutting blade, grinding tools and polishing pads used for concrete, stone, terrazzo.

Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions being boron and nitrogen. Most natural diamonds have ages between 1 billion and 3.5 billion years. Most were formed at depths between 150 and 250 kilometers in the Earth's mantle, and a few diamonds have come from as deep as 800 kilometers. Under high pressure and temperature, carbon-containing fluids dissolved various minerals and replaced them with diamonds. Tens to hundreds of million years ago, they were carried to the surface in volcanic eruptions and deposited in igneous rocks known as kimberlites and lamproites. Synthetic diamonds (artificial diamonds) can be grown from high-purity carbon under high pressures and temperatures or from hydrocarbon gas by chemical vapor deposition. Imitation diamonds can also be made out of materials such as cubic zirconia and silicon carbide. Natural, synthetic and imitation diamonds are most commonly distinguished using optical techniques or thermal conductivity measurements.

Conventional production of diamond tools involves mixing diamond mesh (grit), metal, cobalt powder, nickel prealloyed powders and other materials compacting in a mold. Porosity is then removed, forming a strong solid piece, by hot pressing in graphite or free sintering in an atmosphere controlled furnace.