Jentschite is a mineral that belongs to the borate group. Its chemical formula is Cu2+Al[(OH)3|B(OH)4], and it is commonly found in the oxidized zone of copper deposits. Jentschite typically occurs as earthy, dull-colored masses or as thin crusts on other minerals.
Physically, Jentschite possesses a vitreous to dull luster and can appear in various shades of green, from olive-green to bright green. It has a pale green streak, and its hardness falls between 3.5 and 4 on the Mohs scale.
Chemically, Jentschite contains copper (Cu), aluminium (Al), and boron (B) within its crystal structure. It forms as a secondary mineral resulting from the oxidation of primary copper minerals in hydrothermal environments. Jentschite is often associated with other minerals such as malachite, chrysocolla, azurite, and cuprite.
The name "jentschite" was derived from the German mineralogist and engineer Professor Hans Jentsch, who made significant contributions to the study of copper and lead minerals. The mineral was first discovered in the type locality at the Sa Berritta Mine in Sardinia, Italy.
Jentschite has no significant industrial uses, but it is valued among mineral collectors due to its rarity and distinctive green color. Its unique crystal structure and occurrence in copper deposits make it an intriguing mineral for scientific study and research.
