A single large mass weighing 7.7 kg was found by a rancher named Jim Wingfield about 13 miles SW of Clover Springs in Gila County, Arizona. While setting out salt licks for his cattle, Jim picked up an odd looking rock that was "worth investigating". It turned out to be a rare mesosiderite. The meteorite was subsequently acquired by Harvey Nininger, who eventually sold the main mass to the British Museum of Natural History.
Clover Springs is a moderately metamorphosed mesosiderite, composed of a uniform Fe-metal matrix, containing broken silicate clasts dispersed throughout. Mineral clasts include Ca-poor pyroxene, plagioclase, and olivine, the latter most likely of xenolithic origin (Hassanzadeh et al., 1990). Lithic clasts are predominantly plagioclase-rich, cumulate eucrite fragments. As with all mesosiderites, Clover Springs has experienced low levels of shock, indicating a shock stage of S1/S2. In the classification scheme of Floran (1978) and Hewins (1984), Clover Springs was assigned to metamorphic group 2A (see the Bondoc page for further information about the grouping scheme). The specimen shown above is a 1.35 g partial slice with a fusion-crusted edge. The photo below is an excellent petrographic thin section micrograph of Clover Springs, shown courtesy of Peter Marmet.
click on image for a magnified view
Photo courtesy of Peter Marmet