Formula: CoFe3+2(AsO4)2(OH)2.4H2O
Hydrated arsenate containing hydroxyl, arthurite group
Specific gravity: 3.22
Hardness: 3½ to 4
Streak: White to pale brown
Colour: Yellowish brown to straw yellow

Hydrothermal environments

Cobaltarthurite is a secondary mineral.

At Khder, Bou Azzer, Morocco, cobaltarthurite occurs in cavities in lollingite ore associated with arseniosiderite, scorodite and karibibite.

At Oumlil-East, Bou Azzer, Morocco, cobaltarthurite occurs in vein rock associated with karibibite and parasymplesite.

At the type locality at the Dolores prospect in Murcia, Spain, cobaltarthurite occurs is associated with olivenite and arseniosiderite.