ALMANDINE
Garnet Group
almandine - mineral 51.4.3a.2

	Chemical Formula	Fe3Al2Si3O12
	Composition	Iron aluminum silicate. The iron is frequently replaced by some magnesium and manganese
	Variable Formula	(Fe,Mg,Mn)3Al2Si3O12
	Color	Deep red to reddish-brown, sometimes with a violet or brown hue
	Streak	Colorless
	Hardness	6½ - 8½
	Crystal Forms and Aggregates	(Isometric) Occurs as dodecahedral and trapezohedral crystals, frequently well-formed. Also occurs as dodecahedral crystal aggregates, grainy, massive, and as rounded crystals.
	Transparency	Transparent to opaque
	Specific Gravity	4.3
	Luster	Vitreous
	Cleavage	None. May exhibit parting.
	Fracture	Conchoidal to uneven
	Tenacity	Brittle
	Other ID Marks	Paramagnetic. Becomes magnetic upon heating.
	Other Names	Almandite, Oriental Garnet Almandine is often misspelled "Alamandine" (with an extra "a") Note: Almandine may also incorrectly refer to Almandine Spinel, a variety of Spinel.
	Varieties	Common Garnet refers to brownish-red, opaque Almandine Precious Garnet refers to a deep red, transparent Almandine.
	In Group	Silicates ; Nesosilicates ; Garnet group
	All About	Almandine is a Garnet, belonging to the Garnet group. The Garnet group is a small group of closely related minerals. The members of the Garnet group are isomorphous, and some of them freely intermingle. They vary only slightly in physical properties, and some of them may be so similar that they are indistinguishable from one another without x-ray analysis. The most common members are: Pyrope, Almandine, Spessartine, Grossular, Andradite, and Uvarovite. The minerals in the Garnet group are called "Garnets". All Garnets are hard and many are fit for gem use. Unless articulate, most mineral and gem dealers don't refer to garnets by their true name (i.e. Almandine), but by the name "Garnet". The garnets as a group occur in all colors (except for blue). For more information about garnets, see the Garnet group. Almandine is the most common Garnet. Although only a small amount of this mineral is fit for gem use, it is nevertheless a popular gem. It is the most widely used Garnet in the gem trade. More gems are faceted from Almandine than any other type of Garnet. Some Almandine garnets display asterism when polished as cabochons. Such specimens are known as "Star Garnets". Almandine most commonly occurs embedded in Mica schists. It also occurs in large, single crystals, which are caused from the breakup of the Mica schist due to weathering.
	Uses	Almandine is industrially important for use as Garnet paper, an important abrasive. Almost all Garnet paper is made from Almandine; only a small amount is made from Pyrope. When transparent and colored nicely, Almandine Garnet makes a fine gemstone. Well formed Almandine crystals are very popular among mineral collectors. See the gemstone section on garnet
	Striking Features	Crystal form, color, and hardness
	Popularity (1-4)	2
	Prevalence (1-3)	1
	Demand (1-3)	1
	Distinguishing Similar Minerals	Pyrope - usually deeper red than Almandine, otherwise indistinguishable by ordinary means Grossular - usually lighter in color than Almandine, otherwise indistinguishable by ordinary means Andradite - indistinguishable by ordinary means Spinel - Occurs in different crystals than Almandine Ruby - Harder (9)
	Commonly Occurs With	Biotite, Muscovite, Quartz, Staurolite, Andalusite, Hornblende, Epidote, Magnetite, Nepheline, Leucite, Corundum
	Noteworthy Localities	Almandine is a very common mineral, but seldom occurs in specimens worthy of collections or fit for gems. Only a select few localities are mentioned. Clear, isolated, rounded crystals are found in sand in India; Sri Lanka; and Minas Gerais, Brazil. Fine material has also come from Zillertal, Tyrol, Austria; Telemark, Norway; and Broken Hill, New South Wales, Australia. In the U.S., fine crystals embedded in Mica schists occur in Wrangell Island, Alaska. An enormous deposit, perhaps the largest, exists in the Adirondack Mountains of New York (Gore Mountain, Warren Co.), where this hard material is mined mainly for the production of Garnet paper. Enormous, perfect dodecahedral crystals were found in Salida, Chaffee Co., Colorado. Other U.S. occurences are Spruce Pine, Mitchell Co., North Carolina; Avery Co., North Carolina; and the Thomas Range, Juab Co., Utah. The finest star Garnet (Garnet displaying asterism) is a type of Almandine from Emerald Creek (near Fernwood), Benewah Co., Idaho. Rhodolite, a mixture of Pyrope and Almandine, is widespread at Cowee Creek, Macon Co., North Carolina.
	Picture Icon Links	1. 2.
	Picture Links	1. Single, dodecahedral crystal 2. Crystal in mica schist

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