Isometric (Cubic)
Cuprite is the principal copper(I) oxide mineral and one of the richest Cu ores by mass. Its deep ruby-red color and adamantine luster make it one of the most chromatically striking sulfide-zone collector minerals.
Occurrence in China
Cuprite occurs in the oxidized zones of Tonglushan/Daye (Hubei), Tongling (Anhui), Dexing (Jiangxi) and Yunnan Cu deposits. Large, well-formed cuprite specimens are documented from Mashamba West (Democratic Republic of Congo), Onganja (Namibia), and Bisbee (Arizona).
Identification
Ruby-red translucent cubes/octahedra + adamantine luster + brownish-red streak + association with native copper, malachite, azurite. Distinguish from zincite (hexagonal, orange-red streak) and pyrargyrite (trigonal, lower density).
Collector Notes
Gem-cut cuprite is a connoisseur micro-gem (high RI ~2.85, very soft so collector-only). Crystallized cubes on copper matrix are highly prized — especially “chalcotrichite” hair-like cuprite on copper.