Siderite is derived from the Greek word for iron. Pharmacosiderite lends its good name to a small mineral group called The Pharmacosiderite Group. The Pharmacosiderite Group is a set of closely related arsenates of which pharmacosiderite is the most common member. Color is dark olive-green, yellow, brown or red. Luster is adamantine or vitreous to greasy on fractured surfaces.
Specimens are transparent to translucent.
Crystal System is isometric. Crystal Habits include cubes and more rarely octahedrons, also granular and massive. Cleavage is indistinct. Fracture is conchoidal. Streak is white.