Some Of Our Collection
About California’s Franciscan Complex Stones
These figures have more detail in the book.
The geologic process of Plate Tectonics has been on-going for the past 2½ billion years. In a continuous progression, as the Mid-Oceanic Spreading Center (the driving force of this inexorable process) creates new ocean seafloor it is simultaneously consumed thousands of miles away in a Subduction Zone (Figure 3). Remarkable Franciscan Complex stones and gems originated and were transformed over geologic time by this system.
These figures have more detail in the book.
Tectonized ophiolitic rocks and minerals make up 100% of the Franciscan Complex we see today. Their original once drab seafloor rocks and sediments were transformed as they underwent intense metamorphism deep within the bowels of the Earth. Their extraordinary stories, rock names, minerals and gemstones are described in my book, Tickling The Bones of the Earth.
These figures have more detail in the book.
Most of the Viewing Stones on this website are from the Franciscan Complex. It is the largest geologic formation in the State and stretches from S.W. Oregon into Santa Barbara County. It is over 50,000 feet thick in places, and was created over 150 million years through a continuous geologic process called Plate Tectonics. It is the most studied rock unit on Earth and the geology of most other rock units pale in comparison. Figures 1-3 show how the Franciscan Complex formed through a conveyor-like procession of sea floor sediments that were subducted, tectonized and then burped back to the surface. The Franciscan has gold, gemstones and many kinds of unusual minerals and rocks.