Kupletskite

This specimen features a sharp 4 cm kupletskite crystal intersected by slender black prisms of aegirine, with associated siderite–rhodochrosite solid-solution carbonates, feldspar, and albite. Kupletskite is a very rare potassium sodium manganese iron inosilicate species, prized by collectors for both its scarcity and its well-crystallized occurrences. Mont Saint-Hilaire, Quebec, is the world’s premier locality for this species, producing exceptional examples that have become highly sought-after in the mineral collecting community. This particular piece carries added significance, as it was collected in 1973 by the well-known Mont Saint-Hilaire field collector Peter Tarassoff. With its fine crystal form, classic associations, and notable provenance, this is a desirable specimen for collectors of rare minerals or those specializing in the remarkable mineralogy of Mont Saint-Hilaire.