Adamite on Limonite

Sample of white to slight yellow prismatic euhedral Adamite crystals embedded into earthy brown Limonite. Vitreous lustre. Adamite (Zn2(AsO4)(OH)) is a light yellow, honey-yellow, brownish yellow, pale green, yellowish green, rarely colourless. Lustre is vitreous and streak is white to pale greenish. Hardness is 3 1/2 and cleavage is good in one direction and poor in the second direction. Adamite usually occurs as prismatic or horizontally elongated crystals and can often be drusy crusts or aggregates. Limonite (FeO(OH) x nH2O) can be yellow or brown in colour. Lustre is glassy, silky or dull and streak is yellowish brown. Hardness is 4 to 5 1/2. Limonite usually occurs as earthy, fibrous, botryoidal or stalactitic.