When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This delicate miniature specimen from the Rowley Mine in Theba, Maricopa County, Arizona, features thin, yellow wulfenite blades accompanied by minor orange mimetite crystals. Measuring 26 × 26 × 3 mm and weighing 5 grams, the piece displays vibrant, translucent wulfenite plates with sharp, square to slightly elongated outlines and smooth, glossy faces. Their bright yellow colour and glassy lustre give the specimen an immediate visual impact despite its small size. Scattered across the surface are tiny orange mimetite crystals, providing a complementary warm tone and fine textural contrast.
The Rowley Mine is one of the American Southwest’s classic localities, celebrated for producing intensely coloured wulfenite and richly hued mimetite from its lead–silver–molybdenum ore system. The mine’s oxidised zone developed through prolonged weathering of primary lead minerals, allowing molybdate- and arsenate-bearing fluids to precipitate secondary species. Wulfenite formed as thin, tabular crystals under low-temperature oxidation conditions, while mimetite crystallised later from arsenic-rich solutions, often appearing as microcrystals on or around wulfenite plates. This sequential mineralisation is a hallmark of Rowley material and is reflected clearly in the present specimen.
The specimen’s thin wulfenite blades exhibit excellent translucency and strong internal light transmission, allowing their colour to intensify when illuminated. Their bright surfaces, combined with the gem-like microcrystals of mimetite, create a vivid interplay of tones and textures. The arrangement remains well preserved, showing no significant bruising or edge damage, which is noteworthy given the fragility of Rowley wulfenite. The flat, plate-like structure of the specimen allows close examination of crystal habit and surface detail.
Collected in the 1980s and held within the J & S Mommers Collection, this miniature represents desirable old-time Rowley material from one of Arizona’s most iconic wulfenite localities. Its sharp blades, rich colour, and complementary mimetite association make it an appealing addition for collectors of North American mineral classics or miniature-format cabinet specimens. As both an aesthetic and geological example, it captures the distinct mineralogy and vibrant colour palette that define the Rowley Mine.
