Roselite, Aghbar Mine, Morocco

Mineral Matters #440

Checking back into this week’s Facebook Mineral of the Week Group, minerals of Morocco.

A few days ago, I posted a wendwilsonite. David Joyce commented “I have been told that most roselites are, actually, wendwilsonites”. So this one, labelled as roselite, but to my knowledge unanalysed, may be either one or the other.

For comparison, the roselite formula is Ca₂Co(AsO₄)₂·2H₂O, and the wendwilsonite formula is Ca₂Mg(AsO₄)₂·2H₂O. I think it is likely that there is a complete series between the two end members.

Whichever one it is, the colour is just insane!

Below: Roselite with tan dolomite, Aghbar Mine, Aghbar, Bou Azer District, Tazenakht, Ouarzazate Province, Souss-Massa-Draa Region, Morocco. Width of view 11.5mm.