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| <<Back to Main | ApatiteApatite | Aquamarine and BerylsAquamarine and Beryls | ChrysoberylChrysoberyl | Crystal CollectionsCrystal Collections | DanburiteDanburite | DiopsideDiopside | EnstatiteEnstatite | Feldspar and MoonstonesFeldspar and Moonstones | FluoriteFluorite | GarnetGarnet | Gemstones in matrixGemstones in matrix | Lapis LazuliLapis Lazuli | PegmatitePegmatite | PeridotPeridot | PetalitePetalite | PhenakitePhenakite | Pyrite, Hematite and Iron OresPyrite, Hematite and Iron Ores | Quartz Family: Amethyst, Citrine, Agate...Quartz Family: Amethyst, Citrine, Agate... | Rare Burmese SpecimensRare Burmese Specimens | RubyRuby | SapphireSapphire | ScapoliteScapolite | Sillimanite or FibroliteSillimanite or Fibrolite | SpinelSpinel | TopazTopaz | TourmalineTourmaline | ZirconZircon | Other Fine CrystalsOther Fine Crystals | | Our Top Phenakite Highlight | Phenakite | | | The name phenakite, or the alternate spelling, phenacite, is from a Greek word meaning deceiver, an allusion to its deceptively similar look to quartz. Phenakite is a rare beryllium(Be2SiO4) mineral, but it is found so frequently with precious gemstones that its availablity is not in proportion to its rarity. Basically, Phenacite is found in high-temperature pegmatite veins and in mica-schists associated with quartz, chrysoberyl, apatite and topaz. It has long been known from the emerald and chrysoberyl mine. Phenakite is one of the few silicate minerals that have a trigonal symmetry. This symmetry is far more common among carbonates than among silicates. Phenakite shares the same symmetry with the emerald green silicate dioptase and the fluorescent and closely related willemite. Occasionally, Phenakite is used as a gemstone. Phenacite occurs as isolated crystal which are rhombohedral with parallel-faced hemihedrism, and are either lenticular or prismatic in habit: the lenticular habit is determined by the development of faces of several obtuse rhombohedra and the absence of prism faces. There is no cleavage, and the fracture is conchoidal. The hardness is high, being 7.5 - 8; the specific gravity is 2.96. The crystals are sometimes perfectly colorless and transparent, but more often they are greyish or yellowish and only translucent; occasionally they are pale rose-red. In general appearance the mineral is not unlike quartz, for which indeed it has been mistaken.Fine crystals of phenakite can be perfectly clear and with good hardness, rarity and lack of good cleavage, although somewhat lacking in color and fire, make good choices for gemstones. For gem purposes the stone is cut in the brilliant form, of which there are two fine examples, weighing 34 and 43 carats (6.8 and 8.6 g), in the British Museum. The indices of refraction are higher than those of quartz, beryl or topaz; a faceted phenacite is consequently rather brilliant and may sometimes be mistaken for diamond. | | See all Items in this Phenakite Category |  |
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