Minerals.net

Edenite is a member of the extended Hornblende group. There are several variations of...  More

Edenite is a member of the extended Hornblende group. There are several variations of Edenite with different elemental substitutions. Some of these are recognized as individual minerals, thereby making Edenite a mineral group, with Edenite the dominating member. Edenite is named after the hamlet of Edenville, New York, the type locality where this mineral was first described.
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Elbaite is the most well known and valuable form of Tourmaline . Most of the multicol...  More

Elbaite is the most well-known and valuable form of Tourmaline. Most of the multicolored Tourmalines and almost all of the Tourmaline gemstones are of the Elbaite variety. Elbaite is perhaps the most multicolored mineral, coming in virtually every color of the spectrum. Multicolored crystals of Elbaite are well known and unsurpassed in beauty.

Elbaite has many interesting optical properties. Many green and blue specimens are strongly pleochroic. When viewed through their vertical axis, such specimens appear darker in color than when seen through their horizontal axis. Certain Elbaites exhibit a cat's eye effect when polished into cabochons.
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Emerald is the green variety of Beryl , and its most precious and valuable variety. I...  More

Emerald is the green variety of Beryl, and its most precious and valuable variety. Its intense green color has given it status as an important gemstone throughout the centuries. The color of Emerald is green to emerald-green. The light green form of Beryl is not recognized as Emerald, but rather Green Beryl. The deep color of Emerald is caused by traces of the element chromium, but sometimes also vanadium.

The ancient source of Emeralds in the old world was from Egypt, but their quality was not exceptional. However, the Native South American civilizations such as the Incas have had high quality Emeralds from the mines of Colombia, which have traditionally produced the highest quality Emeralds and continue doing so.

Emeralds can be transparent and gemmy, in which case they are extremely valuable, or they can be in opaque or semi-opaque forms which are much more common and not as valuable.

For additional information, see the gemstone section on Emerald.
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div Enargite is a sulfosalt mineral that is an import ore of copper. Crystals are som...  More

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Enstatite forms series with the rare mineral Ferrosillite Fe sub 2 sub Si sub 2 sub O...  More

Enstatite forms series with the rare mineral Ferrosillite (Fe₂Si₂O₆). Pure Enstatite (without any at all iron) is not common, and pure Ferrosillite (without any magnesium) is extremely rare. A common intermediary member of this series is known as Hypersthene, with a chemical formula of (Mg,Fe)₂Si₂O₆. Although the term Hypersthene has been discredited by the IMA in 1998, it is still commonly used by many reference guides and is labeled as such in many collections.

Pure Enstatite is transparent and lightly colored; the iron content is responsible for the darker colors and increased opacity.
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Epidote is one of the most outstanding display minerals. The finest and most desirabl...  More

Epidote is one of the most outstanding display minerals. The finest and most desirable form of this mineral is in delicate elongated crystals that are extremely lustrous and often interconnected. This form is highly treasured by collectors and creates one of the finest mineral showpieces. The color of Epidote is almost invariably green, in all different shades and tones, with a pistachio color habit being very typical.

Epidote forms a group of related minerals, with the mineral Epidote being the most prominent member of the group. Two uncommon members of the Epidote group are Epidote-(Pb) (which is more popularly known as Hancockite), and Epidote-(Sr). Though often regarded as varieties of Epidote, these two forms are classified by the IMA as individual mineral species.

Epidote is also almost identical in composition to Clinozoisite but lacks significant iron in its structure. It forms a series with Clinozoisite, and in many cases the actual distinction between these two minerals cannot be made. In fact, some specimens from certain localities are labeled as Clinozoisite-Epidote since they are intermediary between these two minerals without an exact determination, or may even contain both these minerals in different parts of a single crystal.
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Epistilbite is a rare member of the zeolite group. It has a very similar chemical mak...  More

Epistilbite is a rare member of the zeolite group. It has a very similar chemical makeup to Stilbite, and can be difficult to distinguish from Stilbite. Epistilbite is named from the Greek Epi which means "similar" and Stilbite, due to the similarity of this mineral to Stilbite. Epistilbite is not dimorphous with Stilbite, despite its prefix Epi which often implies a dimorph. Interestingly, Epistilbite it dimorphous with a different zeolite, the rare Goosecreekite.

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Epsomite most commonly forms as efflorescence on cave walls from deposition of materi...  More

Epsomite most commonly forms as efflorescence on cave walls from deposition of material from saline springs. It generally is formed in arid regions and in dry caves which protect it from rain and moisture, for otherwise it dissolves. Epsomite may also form efflorescence in tunnels of sulfide mines from the deposition of sulfur and magnesium-rich water during mining operations. Itis not commonly seen in collections, for it lacks appeal, is very fragile, and must be kept in dry areas to prevent it from disintegrating.

Epsomite forms a solid solution series with the following similar sulfates: Morenosite, a hydrous nickel sulfate (NiSO₄ · 7H₂O), and Goslarite, a hydrous zinc sulfate (NiSO₄ · 7H₂O).  Hide

Erythrite is a deeply colored reddish or pink mineral, with its distinctive color cau...  More

Erythrite is a deeply colored reddish or pink mineral, with its distinctive color caused by its cobalt content. Erythrite is the end member of a series with Annabergite, with Erythrite being the cobalt-dominant member and Annabergite being the nickel-dominant member. Erythrite is named from the Greek erythros, red, in reference to the hue of this mineral.
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div Euclase is a rare and highly desirable mineral among collectors. It can form in e...  More

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