Iodargyrite
Image: Robert M. Lavinsky (CC BY-SA 3.0)
Mineral NameIodargyrite
Chemical FormulaAgI
Mohs Hardness1.5
Crystal Systemhexagonal
Lusteradamantine
Streak Coloryellowish-white
Cleavagenone
Fractureconchoidal
Specific Gravity5.6
Colorsyellow, greenish-yellow, brown, colorless
Transparencytransparent
Type LocalityBroken Hill Proprietary Mine (Proprietary Mine; BHP Mine), Broken Hill, Yancowinna County, New South Wales, Australia
Mineral GroupHalides
Usescollector's mineral, minor silver ore
Associated Mineralssilver, cerussite, anglesite, smithsonite, mimetite, native copper
Rarityuncommon
Description
Iodargyrite typically forms small, translucent, yellowish-green hexagonal crystals, often tabular or prismatic, sometimes appearing as waxy coatings or masses.
Geological Context
This mineral is a secondary halide, forming in the oxidized zones of silver deposits where silver-bearing solutions react with iodide ions, often in arid environments.
