Euclase: Euclase is a silicate with a monoclinic crystal system. It is considered a very rare gem of light bl... (read full)

Epidote: Epidote is widespread, forms a continuous series of minerals, ending with clinozoisite, which contai... (read full)

Enstatite: Enstatite is the most common silicate under the Orthopyroxene group in the larger classification of ... (read full)

Emerald: Emerald is the most prized variety of the mineral Beryl. It sometimes fetches higher prices than dia... (read full)

Dumortierite: Dumortierite is a variety of gemstone of basic aluminum borosilicate with an orthorhombic crystal s... (read full)

Dravite: Dravite also called Brown Tourmaline is a sodium magnesium-rich mineral in the Tourmaline group of s... (read full)

Dolomite: Dolomite is similar to calcite and sits along side it in limestone. It usually occurs as a secondary... (read full)

Dioptase: Dioptase is a relatively rare emerald-green mineral, sometimes tinged bluish or blackish. Crystals a... (read full)

Diopside: Diopside is a type of Clinopyroxene, which are abundant, rock-forming minerals. These are embedded a... (read full)

Diamond: In fact Diamond is the only gem material comprised of a single chemical element: pure carbon, like g... (read full)