Diamond type
Diamond type is a method of scientifically classifying diamonds by the level and type of their chemical impurities. Diamonds are separated into four types: Type Ia, Type Ib, Type IIa, and Type IIb. The impurities measured are at the atomic level within the crystal lattice of carbon atoms and so, unlike inclusions, require an infrared spectrometer to detect.
Gemstones in the Bible
Aben-Esra and Abarbanel translate "yhlm" as "diamond"; but "yhlm" was demonstrated above to be beryl. Diamond is made up of pure carbon, mostly of a white transparent colour, but sometimes tinted. White diamond is often regarded as the most precious because of its beauty and rarity.