Description
Specimens of this mineral from the Ojuela mine have actually been determined (Moore, 2003) to have an intermediate composition between Köttigite and Parasymplesite. This material is therefore a hydrated zinc-iron arsenate and is a member of the Vivianite Group which is why the crystal morphology looks so similar. Although found at numerous localities, by far the best crystals are found at the Ojuela Mine in Mexico and came out in the 1970´s and 1980´s. These yolk-yellow, slightly altered and also blue-gray (at the periphery) lamellar to slightly fanned crystals are unusually sharp and well-formed. They display very nicely, perched on a "limonite" matrix. A significant display miniature for the species!