Moissanite

Near-colourless, slightly oily looking man-made material that is often used to imitate diamond – a diamond simulant.

Moh’s Scale

Scale from for classifying the relative hardness used for gemstones, based on the ability of harder gemstones to scratch softer ones. Moh’s scale ranges from 1 to 10, with 10 being the hardest. Diamonds are the only material on earth to rate as a 10.

Master Set

Set of certified and registered diamonds, with known colours against which other diamonds are compared to establish their colour. A diamond master set is neccesary  for accurate colour grading. A first generation diamond master set is available to any diamond merchant or jeweller.

Marquise Cut

Diamond cut or shaped into an oval with pointed ends. Also called a ‘navette,’ which is the French word for “little boat,” as the shape is similar to that of a boat’s hull.

Loupe

Hand held magnifying lens. Diamond clarity must be graded with a 10x loupe that is corrected for spherical and chromatic aberration.

Loose Diamond

Diamond that is not mounted in jewellery. Diamond certification is not possible when the diamond is set in jewellery, as none of the four c’s can be accurately assessed – only estimates are achievable.