The differing charges on the irons causes a very weak magnetism that might turn the needle ofa compass. This can be very diagnostic since these two minerals can appear very similar to many other black, monoclinic, submetallic minerals. The magnetic effect is greater in babingtonite because it has more divalent irons. Color is brown to black. Luster is vitreous, submetallic to dull.
Crystals are generally opaque but thin crystals or splinters can be translucent.
Cleavage is good in one direction and perfect in another, these are pinacoidal but are at near right angles to each other giving the appearance of rectangular prisms. Fracture is uneven to subconchoidal. Hardness is 5. Streak is brown to gray. Sometimes very weakly magnetic.