MORENOSITE

    Class : Sulfates, chromates, molybdates
    Subclass : Hydrated sulfates
    Crystal system : Orthorhombic
    Chemistry : NiSO4 7H2O
    Rarity : Fairly common

Morenosite is a secondary nickel sulfate that is found in encrustations and efflorescences in outcrops of nickel deposits, as well as in cracks in altered nickel ores. With the replacement of Ni by Mg, a complete solid solution is obtained with epsomite. Very soluble, it only keeps well in dry or cold, even icy, climates, which explains its abundance in Canadian nickel deposits. It was named in honor of the Spaniard Antonio Moreno Ruiz, Chemist at the Academy of Natural Sciences in Madrid. Morenosite is a clear grass green but becomes paler as its magnesium content increases.

Main photo : Morenosite from Jáchymov, Czech Republic © Bahuslav Bures

Morenosite in the World

Morenosite is a fairly common oxidation mineral discovered in notable quantities in Sudbury (Ontario, Canada). It exists elsewhere in more modest quantities, notably in outcrops of the mines of Marbridge (Quebec), Avoca (Ireland) and also Jachymov (Czech Republic), as well as in the nickel-bearing serpentinites of Val Malenco (Lombardy, Italy).

Right photo : Morenosite from Les Perrères Dam, Valtournenche, Aosta Valley, Italy © Michel Arliguie


Morenosite in France

In France, morenosite is known at Cap Garonne (Var).

Twinning

No twin known for this mineral species.

Fakes and treatments

No fakes recorded for this mineral species.


Hardness : 2 to 2.5
Density : 1.953
Fracture : Conchoidal
Streak : White to slightly green

TP : Transparent
RI : 1.467 to 1.492
Birefringence : 0.025
Optical character : Biaxial -
Pleochroism : None
Fluorescence : None

Solubility : Water

Magnetism : NoneRadioactivity : None