Humodetrinite

Humodetrinite is a rare and poorly characterized mineral that belongs to the phosphate group. It was first identified in 1966 at the type locality of the Humodete mine in the Czech Republic, though its occurrence remains limited and debated among mineralogists. The mineral’s name derives from its association with the Humodete locality and its chemical composition, which includes elements like aluminum, calcium, iron, and phosphorus.

Chemically, humodetrinite is described as a complex phosphate, with a general formula often approximated as CaAl₃(PO₄)₂(OH)₃·H₂O, though exact stoichiometry remains uncertain due to its scarcity and potential instability. It typically forms as a secondary mineral in hydrothermal veins, often found in close association with other phosphates such as variscite, crandallite, and rockbridgeite. The mineral exhibits a white to pale yellow color and is usually translucent with a vitreous luster. Its crystal structure is poorly defined, with reports suggesting a possible layered or fibrous habit, though specimens are often massive or granular.

Due to its rarity and ambiguous classification, humodetrinite has not been widely studied. Some researchers question whether it represents a distinct mineral phase or merely a transitional or altered form of more common phosphates. Specimens are primarily found in the Czech Republic, particularly in the Jáchymov (Joachimsthal) region, where historical mining activities have yielded a few documented occurrences. Beyond its type locality, reports of humodetrinite are sparse, and its presence in other regions remains unverified.

Given its limited occurrence and scientific ambiguity, humodetrinite holds minimal commercial or industrial significance. It remains of interest primarily to mineralogists and collectors specializing in rare or exotic phosphate minerals. Further research, including advanced analytical techniques, may clarify its true nature and potential distinctiveness as a mineral species.