Milarite and Biotite

Unknown Owner

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Milarite is a rare hydrated potassium-calcium-aluminum-beryllium silicate that is found in select granite pegmatites, but specimens are even more rare, for the collector. This rich cluster is composed of nearly a dozen, soft lemon-yellow, prismatic crystals in sculptural growth. The crystals have well developed prism and pinacoid (flat top) faces with a satin luster with terminations that are gemmy, with the remainder of the crystal translucent to slightly opaque. The Milarite crystals are from 3 mm to 1.5 cm in length and the cluster has good composition. It is also associated with several, well-formed and shiny, silvery-brown, platy Biotite crystals on the back of the piece. These Milarites are very respectable in size for the species. The crystals are in excellent condition with only a little contacting at the bottom where it was removed from the pegmatite pocket. This is a significant Brazilian piece, as most are singles and matrix specimens or clusters are almost never seen for sale. Probably from the 1980s-early 1990s.