The 1,024 th meeting of 

The Mineralogical Society


Southern California


The White Rock Quarry,

Clay Center, Ottawa County, Ohio 

      presented by  Christopher Stefano.

Friday, April 12, 2024 at  7:30 pm.

See program notes below

Visitors are always welcome

About us…

The MSSC is a member of the California Federation of Mineralogical Societies and is dedicated to the dissemination of general knowledge of the mineralogical and related earth sciences through the study of mineral specimens.  We are a scientific non-profit organization that actively supports those endeavors through public outreach, field study and related programs.

For more information

Notice of July 29, 2023 regarding Mojave Trails National Monument.  Reprinted with permission from San Diego Mineral & Gem Society.  Great commentary in the notice by its author, Lisbet Thorensen, SDMG’s Public Lands Representative.  Thank You, SDMG and Lisbet.  Angie Guzman, MSSC President.Please click here to read article and commentary.

Program Notes: Friday, April 12, 2024 at 7:30, join us for “The White Rock Quarry, Clay Center, Ottawa County, Ohio”  Presented by  Christopher Stefano.

This talk will discuss the geology, history and fine mineral specimens of one of Ohio’s oldest and most famous localities. Known for its “root beer” brown fluorite, as well as fine sphalerite and celestine specimens, Clay Center has been producing specimens since the Victorian era. The talk summarizes the article by Chris Stefano and Jamison Brizendine published in the Mineralogical Record in 2020.

Dr. Chris Stefano has had a lifelong passion for geosciences. He completed his bachelor’s degree in geology at Kent State University in 2004 and was then admitted to the Ph.D. program at the University of Michigan where he studied the role of water in basaltic eruptions in the Yellowstone Hotspot in Washington, Oregon, Idaho and Wyoming. By the time he graduated in 2010, Chris had amassed a large mineral collection and was an active mineral dealer. He was hired in 2011 to carry out an inventory and assessment of the University of Michigan’s mineral collection, including a discussion of the history of the collection, which was published in Rocks and Minerals magazine in 2013. Chris became the Associate Curator of Michigan Tech’s A. E. Seaman Mineral Museum later in 2013. During that time, he completed several publications on various topics in specimen mineralogy and petrology, as well as oversaw several large acquisitions to the collections; including the Michigan Mineral Alliance, under which the University of Michigan collection has been added to the A. E. Seaman Mineral Museum’s holdings. In 2019, he joined the staff of The Mineralogical Record as an editor and has published many articles dealing with the American Midwest and other topics. Many more are on the way. His interests are very broad, spanning geochemistry, petrology, mineralogy and the history of science. He is particularly interested in the minerals of the American Midwest and Arkansas’ Magnet Cove district, and has significant field experience in these areas.  Chris’s other hobbies include cooking and board games.


MSSC members will be automatically on the invite list each month.

Non Members, you must request to attend the MSSC zoom meeting every month Email our Programs chair, Rudy Lopez at  no later than the Thursday before the scheduled meeting   Please include “ZOOM Meeting” in the subject line of your response. We will send you the meeting link.

Upcoming Events

all events, except field trips are via  ZOOM

  • May 10, 2024:  Erin Delventhal- Quartz in New Mexico
  • June 14, 2024: Les Presmyk – TBA likely on Mexico minerals
  • Board Meeting, Sunday April 14, 2024 at 1:00 pm
  • CFMS/AMS Show in Ventura, May 24-26.
  • August 24, 2024: MSSC Picnic-Technology Park, Caltec Campus Watch for more details

The MSSC is pleased to offer the updated 2023 edition of Bob Pedersen’s X- Dana 

X-Dana Mineral Spreadsheet