Diadochite Field of view: 4 mm Locality: Hagendorf South, Hagendorf (Waidhaus), Bavaria, Germany Description: Yellowish, spherical aggregates of diadochite on a matrix — Photo: Henk Smeets – tomeikminerals.com · CC BY 4.0
Diadochite
A secondary iron phosphate-sulfate formed by weathering; its well-crystallized form is the recognized species destinezite.
Intro adapted from Wikipedia (CC BY-SA).
Diadochite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Fe³⁺₂(PO₄)(SO₄)(OH)·6H₂O.
It is a member of the Amorphous structural group.
Key properties: Mohs hardness 3–4; specific gravity 2–2.4.
IMA symbol Ddc, grandfathered status — known before the IMA’s founding, named in 1837.
Found as a secondary mineral in gossans and some coal deposits, formed by sulfate-rich solutions acting on earlier phosphates, may be post-mine; in cave deposits, the phosphate derived from guano.
It is found associated with Delvauxite, vashegyite, pitticite, melanterite, vivianite, wavellite, leucophosphite, phosphosiderite, ferrostrunzite, beraunite, mitridatite, rockbridgeite.
Its name comes from the Greek for a successor, as it typically is formed from earlier phosphates. Destinezite is visibly crystalline, triclinic Fe2(PO4)(SO4)(OH)·6H2O.