Mineral, Cu2CO3(OH)2; sp. gr. 3.9–4.0; hardness 3.5–4.0; monoclinic; bright green; pale green streak; in fibrous condition with a silky lustre, crystals with adamantine or vitreous lustre; crystals very rare, and it is usually found as botryoidal, encrusting masses with bands of varying colour, and frequently in a fibrous, radiating habit; common secondary mineral in the oxidized zone of copper deposits, associated with azurite, native copper, and cuprite; soluble with effervescence in dilute hydrochloric acid. It is often used for ornaments and pigments, and as an ore mineral for copper. See spessartite.
Subjects: Arts and Humanities — Earth Sciences and Geography.