A lot of very small silvery nuggets of the extremely rare intermetallic Au-Hg mineral aurihydrargyrumite (IMA 2017-003) intermixed with other grains of arsenopyrite in a sample that was completely analyzed by SEM/EDS. From Modderfontein Mine, Benoni, Ekurhuleni District, Gauteng Province, South Africa. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Aurihydrargyrumite
Aurihydrargyrumite is an IMA-recognized mineral species in the native element class, with the chemical formula Au₆Hg₅.
It crystallizes in the hexagonal crystal system (space group P6_3/mcm).
Key properties: Mohs hardness 2.5; specific gravity 16.86; Silvery white streak; Metallic luster.
IMA symbol Ahg, IMA status: approved, named in 2017.
Found in a fluvial placer, with sediment derived from a terrain of mafic, pelitic, and psammitic schists and greenstones, as coatings on gold grains.
It is found associated with Gold, ilmenite, magnetite, chromite, zircon, scheelite, iridium, osmium, irarsite.
Reflects the Latin roots for its components, aurum (gold) and hydrargyrum (mercury).