Editor's Note: This is the latest installment of the rockhounding travels of Thomas Farley, as he gathers materials for a book about rockhounding in the southwestern United States. In this installment he shares a bit about his exploration of The California Rock Garden, located near the Earth and Physical Sciences buildings of the University of California Davis campus. The focus of this blog post is a marble boulder of rhodochrosite at the California Rock Garden.
Post and Photos by Thomas Farley
Beautiful marble boulder from the Lucerne Valley in San Bernardino County in California. Solidly in the Southwest. The red-pink color is due to rhodochrosite.
“Originally a limestone formed in a tropical sea, this rock was later metamorphosed at high pressures and temperatures into marble during mountain-building processes.”
Well developed rhodochrosite crystals easily sell into the hundreds of dollars. Rhodochrosite without crystal faces fetch only a little money, with the material looking like sad red lumps. It is only with a defined crystal form, in this case rhomboidal, that this mineral goes from being merely a formless rock to a prized collectible.
Rhodochrosite slabs for cabbing are available, but nothing sells for more than crystal forms. Condition is everything in the mineral hobby and the beginning collector may have to settle for micro mounts before affording anything better. Like antique cars, the finest examples belong to museums and private collectors with extraordinary budgets.
The only way around this, perhaps, is to self-collect. But that relies upon access to open ground.
We will be sharing posts and portions of posts penned by Thomas during his journeys, as a means of sharing in the spirit of adventure. For more information about Thomas, visit his site https://southwestrockhounding.com/blog.