Wednesday, April 12, 2023

The Mines and Minerals of Montgomery County

Join us as Ron Sloto presents on Montgomery County’s mineral industry which has a long history dating to the earliest years of colonization and continues today. During a history spanning more than 300 years, some of the mineral deposits were successfully exploited, and some were never economically viable. Mineral production today consists of crushed stone and some building stone. In the past, Montgomery County was a leading producer of iron ore and pig iron. It also produced copper ore and lead ore. Beginning in the late 1600s, production of lime became an important industry supplying lime for agricultural use and for mortar and cement. The same rock formations provided magnesia for the large asbestos industry. Prior to 1840, Montgomery County was a major producer and exporter of marble. Portland cement was manufactured from locally quarried limestone for several decades. Other mineral products include refractories, sand, clay, and bricks.

The Perkiomenville quarry in Perkiomenville, Montgomery County, PA, in 2018. Photo by Ron Sloto

Lectures are at 7:30PM EST

Lectures are FREE and open to the public.

In-person and on Zoom. Please click here to log-in.

Abington Friends Meeting, The John Barnes Room at 520 Meetinghouse Road, Jenkintown

Masks are recommended but not required to attend the lecture.

The lecture series is sponsored by a grant from the Jenkintown Lyceum and all programs are offered free of charge. For more information, please call the Old York Road Historical Society at 215–886–8590.

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Ron Sloto is on the research faculty of West Chester University. He serves as the curator for the mineral collection at the University and is the Director of the WCU Geology Museum. He conducts research on the mineralogy of southeastern Pennsylvania. Ron retired from the U.S. Geological Survey after a 41-year career that included publication of over 80 reports, journal articles, and abstracts. The HYSEP hydrograph-separation computer program he developed is in worldwide use. Ron has been a mineral collector since the age of 5 and also has a keen interest in history. He has published a book on the mining history and mineralogy of Montgomery County (“The Mines and Minerals of Montgomery County, Pennsylvania”), as well as Chester, Berks, and Bucks Counties. All of the books are available on His most recent publication is the journal article “Phosphate Minerals from Lime Ridge, Snyder County, Pennsylvania” in the September-October 2022 issue of The Mineralogical Record.

In-person and on Zoom. Please click here to log-in.