Identity
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Name & Human History
Etymology
Axinite is named for its shape. The word comes from the Greek for axe, because its crystals grow as thin, sharp wedges that look just like the edge of an axe blade. The French scientist Rene Just Hauy gave it the name in 1797. The kind here, axinite-(Fe), is the iron rich member of a small family, and the iron is what tints it a warm clove brown.
Today
Axinite is mostly a collector's mineral, rarely cut for jewelry because it is brittle and hard to work. What collectors love is the crystal shape and the rich color. Hold a brown axinite to the light and turn it, and the color seems to shift between brown, plum, and a hint of violet. That shifting color, seen from different angles, is one of its signatures.
Geology & Occurrence
Formation
Axinite forms where hot, boron rich fluids meet and alter rock, often at the contact between granite and limestone. It is a borosilicate, a mineral built around the rare element boron, which is why it appears in these special settings. It grows as sharp wedge shaped crystals lining cracks and pockets, sometimes in fan like groups.
Notable Localities
The classic source for fine axinite is Bourg d'Oisans in the French Alps, which has supplied collectors for generations. Excellent brown crystals also come from Dal'negorsk in Russia and from Pakistan. Good pieces turn up in Japan, Mexico, and parts of the United States as well, usually in rocks reshaped by heat near granite.
Axinite holds a quiet bit of magic. It is both piezoelectric and pyroelectric, which means it can build up an electric charge when it is squeezed or simply warmed. Heat a crystal and it will draw bits of dust and lint toward it, much the way amber does when rubbed. Its dark brown color can fool the eye for smoky quartz, but that wedge shape and its charge give it away.
