The Sweet Home mine in Colarado's Alma mining district has been known since 1872 for silver, but more recently the mine has become famous for producing top quality rhodochrosite crystals. The best qualities are well-formed, translucent to transparent rhombohedrons with intense orange red color. The colors are stunning red like some of the top quality rubies.
Rhodochrosite is soft and has perfect cleavage in three directions so faceting the stone is difficult. The cut yield can range between 5% and 20% depending on the size and shape of the rough and the experience of the cutter. The smaller sizes may be calibrated in 0.5mm increments as oval, round, princess, cushion, emerald and trilliants. Cabochons both calibrated and free sizes can also be polished based on the quality of the rough. Cabochons displaying chatoyancy with four rayed stars have also been found. It is believed that most faceted stones are untreated, while some of the cabochons may be stabilized during the cutting process.
The cut rhodochrosite is being sold by Mr Van Wagoner, Beija-flor Gems, Haiku, Hawaii. They expect the stocks to last for two or three years, after which few stones will be available in the market.
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