Photo of Axinite in Processed & Rough Form
Axinite is a mineral with a hardness of 7 out of 10 on the Mohs scale of mineral hardness [?]. These Triclinicly structured gems are made of complex borosilicate, their full chemical compound being CaFeMgBal2Si4O15(OH).
Axinite is a honey brownish to dark brown gem that is named after the axe head like crystal structures that are usually found. It is usually found in and around granite deposits, and is often mistaken (and sometimes sold by mistake) as smokey quartz.
The gem is piezoelectric and because of this has been used to remove hair and lint from unwanted objects. A negative side effect of this is that it will also gather up dust sitting on your shelf much faster than the other objects.
Axinite has been regularly mined in the United States (California and New Jersey), Brazil, England, Mexico, France, Tanzania, and Sri Lanka.
Quality non included properly cut axinite can sell for $100 a carat or more, most specimens however do not sell for this much.
Colors vary but are for the most part brown with a hint of purple or violet, and sometimes even hints of blue.
Why do Axinites show such unusual colors?
Axinite's complex chemical composition creates distinctive brown-violet to plum colors rarely seen in other minerals. Each variety (ferroaxinite, magnesioaxinite, tinzenite) shows slightly different color ranges due to varying iron and manganese content.
What makes Japanese Axinite special?
Japanese axinite crystals, particularly from Obira, are prized for their exceptional transparency and deep violet-brown color. These specimens often produce the finest faceted stones and show superior clarity.
Why is Axinite rarely used in jewelry?
Despite its beauty, axinite's perfect cleavage in three directions makes it fragile for jewelry use. Most specimens are preserved for mineral collections. When faceted, stones require protective settings and careful handling.
How can I identify genuine Axinite?
Look for distinctive flattened wedge-shaped crystals, strong pleochroism (color change when viewed from different angles), and characteristic violet-brown color. The complex crystal form is often a key identifying feature.
Are green Axinites natural?
Yes, some axinites (particularly tinzenite variety) can show greenish colors, though these are rare. Most valuable specimens show the classic violet-brown to clove-brown colors typical of ferroaxinite.
What causes the strong pleochroism?
Axinite's complex crystal structure creates dramatic color changes when viewed from different directions. This pleochroism can show honey-brown, violet, and olive-green colors in the same stone depending on viewing angle.
What determines Axinite's value?
Value depends on color intensity, transparency, crystal form quality, and size. Well-formed crystals showing strong pleochroism and good transparency command premium prices. Historic specimens from classic locations are particularly valued.
The specific gravity [?] for Axinite is 3.28, its refractive index [?] is 1.67-1.70, and its double refraction [?] is 0.011.
History
Industrial Usages
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