Borcarite xls; Charcas, S.L.P., Mexico; 1 lot with 20 pieces, unique

Borcarite crystals from Charcas, San Luis Potosí, Mexico – 1 lot with 20 pieces, unique

This lot features well-formed crystals of the rare boron mineral borcarite from Charcas, Mexico. The bluish-green to turquoise crystals appear on dark brown to black matrix, partially lining small cavities or forming patchy crusts. Some specimens show excellent crystal quality with glassy luster and partly translucent areas.

Borcarite is a rare borate-carbonate mineral that forms under hydrothermal conditions in zinc and lead ore deposits. The locality of Charcas in San Luis Potosí is among the world’s most significant occurrences for this species. Specimens of this quality and quantity are very rarely offered and are highly sought after for systematic collections or specialized boron mineral suites.