This Old Rock was founded in 1998, to study minerals and share their wonderment.  


 In 1999 we purchased a remote parcel of land with a small surface deposit of quartz crystals.  This deposit has developed over the years to a remarkable series of crystal caverns.   What makes this endeavor intriguing, in addition to the giant quartz crystals, is their unusual and amazing crystallography.  

     John's interest in rocks began at an early age.  After 30 years in the Restaurant industry he returns as our Project Manager. Experienced in advising clients and is known to say "Find a need and fill it".   We have a Select Inventory of Show-stoppers guaranteed to inspire, engage, and excite your audience!                                                   

Founders John and Catherine French


Our interactive outreach program is the motivation for this ever expanding and delightful discovery adventure.

A group of  students explore and learn.  The big rock has been named California's official "Friendship Rock" and has been shared with several thousand eager earth scientists.  Materials and program inquiries are welcome.


                                                                                      AboutAboutCuriosity and discovery.

This young citizen scientist used his camera as a microscope.    We also use an inexpensive usb microscope to look at what was created inside this fault-line geological event.   The hydro-thermal environment allowed for the deposition of almost any mineral to be  captured in the rocks.

What do you see?     1) Pyrite cubes  2) Rutile  3) Tourmaline  4) Cosalite 5) Amethyst 6) Copper  7) Co2 bubbles




We are honored with this detailed description by Dr. Lavinsky.


We know this is a strike-slip fault, but how many miles deep into the crust does it go?


  1. One mile
  2.  Six miles
  3. One hundred miles