Signature Specimen: The Alma King Rhodochrosite At the Denver Museum of Nature & Science

Abstract

is a rhodochrosite specimen known as the Alma King. Its large size, clarity, rhombohedral shape, and cherry-red color make it one of the most glamorous in the mineral kingdom. Perched atop a white carpet of thin quartz crystals, the bold crystal’s angular margins are accentuated by the jagged, irregular shape of the slab upon which it lies. Clusters of blue fluorite, black sphalerite, and yellow calcite occur elsewhere on the slab and provide a striking color contrast for the Alma King rhodochrosite and the other smaller rhodochrosite crystals that adorn the specimen (fig. 1). One does not need to be a mineral collector to be captivated by its beauty, nor to pick up on the “red, white, and blue” theme carried through the piece. Although the Denver Museum of Nature & Science (DMNS) (fig. 2) exhibits many fine specimens, including local amazonite, gold, and aquamarine, it is the Alma King that visitors might remember most. It was mined from a tetrahedrite-rich vein in the Sweet Home mine under Mount Bross—not far from Alma, the highest town (at an elevation of 10,578 feet; 3,225 meters) in North America (figs. 3 and 4). At the Denver Museum of Nature & Science CARL A. FRANCIS Maine Mineral & Gem Museum PO Box 500 Bethel, Maine 04217 cfrancis@mainemineralmuseum.org