Bronze crystals of the extremely rare Fe-Mg sulphide mineral haapalaite from the type locality in Kokka mine (Outokumpu, North Karelia, Finland) and one of the very few localities known worldwide. Very rich specimen of this very rare species for the quantity of microcrystals and crystal aggregates present. — Photo: David Hospital · CC BY-SA 4.0
Haapalaite
Haapalaite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula 2[(Fe,Ni)S]·1.61[(Mg,Fe)(OH)₂].
It crystallizes in the hexagonal crystal system. It is a member of the Valleriite structural group.
Key properties: specific gravity 3.57; Metallic, strong luster.
IMA symbol Ha, IMA status: approved, named in 1972.
Occurs as thin scales in the Kokka serpentine and in carbonate; rarely in chrysotile.
It is found associated with Pentlandite, maucherite, chalcopyrite, magnetite, chromite, lizardite, calcite.
In honor of Paavo Haapala (1906–), Chief Geologist of the Outokumpu Company, Finland.