Mottramite is the rarer of the two minerals. Mottramite can form sparkling crusts that have a nice luster and striking green color. Its rarity and attractiveness are the reason for the typically high prices one would expect to pay for a fine specimen. Color is typically various shades of green, rarely black. Luster is resinous.
Crystals are transparent to opaque.
Cleavage is none. Fracture is conchoidal to uneven. Hardness is 3 to 3.5. Streak is green. Associated Minerals are descloizite , malachite and other secondary ore minerals.