Iodargyrite (also called iodyrite) is a silver mineral, having composition AgI. It is found in oxidized parts of silver deposits. Most of this photograph is lim — Photo: Nessa Eull · CC0
Iodargyrite
Natural silver iodide — the rarest of the 'horn silver' halides after chlorargyrite and bromargyrite.
Intro adapted from Wikipedia (CC BY-SA).
Iodargyrite is an IMA-recognized mineral species in the halide class, with the chemical formula AgI.
It crystallizes in the hexagonal crystal system (space group P6_3mc). It is a member of the Wurtzite structural group.
Key properties: Mohs hardness 1.5–2; specific gravity 5.69; typically yellow; Yellow, shining streak; Resinous to adamantine, pearly on cleavage surfaces luster; optically uniaxial.
IMA symbol Iag, IMA status: approved, named in 1962.
Found as a secondary mineral in the oxidized portions of silver-bearing deposits.
It is found associated with Silver, acanthite, chlorargyrite, bromargyrite, cerussite, “limonite”.
The name comes from IODine and the Greek for silver, ARGYRos, in the composition.
Collections: Collector Favorites, Rare & Remarkable.