Paceite
Paceite is an IMA-recognized mineral species in the organic mineral class, with the chemical formula CaCu(CH₃COO)₄·6H₂O.
It crystallizes in the tetragonal crystal system (space group I4/m). It is a member of the Acetate structural group.
Key properties: Mohs hardness 1.5; specific gravity 1.472; Pale blue streak; Vitreous luster; optically uniaxial.
IMA symbol Pac, IMA status: approved, named in 2001.
Formed in ferruginous gossan by reaction of oxidized zone metallic minerals with decaying vegetable matter provided by leaf litter and possibly mine timbers.
It is found associated with Hoganite, linarite, malachite, azurite, cuprian smithsonite, cerussite, goethite, hematite, quartz.
The mineral was named to honor Frank L. Pace (1948–), Broken Hill, miner and collector of Broken Hill minerals, who first noted the mineral.