Ruby, Sapphire, Kyanite, Sillimanite and Iolite at Palmer Canyon Wyoming

After finding iolite in Palmer Canyon, other discoveries were made. These included a half-dozen ruby-sapphire (corundum) occurrences, and a couple of kyanite deposits. I was amazed at how many gemstones, diamonds, and gold deposits had been overlooked.

But there are still more gemstone deposits to find. Based on geological models, many more deposits of diamond, ruby, sapphire, garnet, zircon, spinel, kyanite, varisite, minyulite, emerald, gold, helidor, aquamarine, staurolite, sillimanite, iolite, opal, agates, jasper, specularite, labradorite, chromian diopside, etc, are likely. There is even one deposit listed as gem-quality garnets in the Hartville uplift, that has yet to be investigated. 

As you think about rubies and sapphires, keep three rock types in mind while prospecting in Montana, Wyoming Colorado, Utah, and California: skarn, vermiculite schist, and serpentinite! These are possible host rocks for ruby and/or sapphire. To find out more about these, characteristics of ruby, sapphire and their host rocks are described in a couple of recent books.

Kyanite-ruby-vermiculite schist, Palmer Canyon, west of Wheatland, Wyoming.

A >18,000-carat sample of ioite. The iolite is partially altered to limonite and the specimen 
includes milky quartz. Collected at Palmer Canyon, Wyoming (photo by the author).

Specimens of vermiculite schist filled with purple-red ruby, Palmer Canyon.

Iolite in schist, Palmer Canyon, Wyoming (photo by the author)

Excellent iolite (more than a thousand carats) from an undisclosed Wyoming locality
(photo by the author)

Kyanite schist, West Cooney Hills, Wyoming

Beautiful iolite rough in gneiss from undisclosed locality, Wyoming

Pink sapphire in vermiculite schist from Palmer Canyon, Wyoming (photo by the author).