Bladed stibnite crystal spray on quartz matrix — Jiangxi, China. Stibnite (Sb2S3, antimony sulfide) is the most important ore of antimony, and China currently produces the overwhelming majority of the world's supply. The Wuning and Xikuangshan districts in Jiangxi and Hunan are the classic collector localities — they've produced the finest stibnite specimens on Earth, with crystals sometimes reaching half a meter in length. What's unique about stibnite is its low melting point (just 550 C) — low enough that ancient Egyptians actually used powdered stibnite as "kohl" eyeliner, and historians suspect some early metallurgists accidentally produced antimony metal by smelting the ore in campfires. Two collector notes: those gorgeous prismatic crystals are softer than many people expect (Mohs 2) and deform easily, and stibnite slowly tarnishes from bright silver-metallic to a duller blue-grey over years of air exposure.
