QUINCY, CA--(Marketwire - Dec 15, 2011) - Plumas Bank, a subsidiary of Plumas Bancorp (NASDAQ: [ PLBC ]), has partnered with Cornerstone Industrial Minerals Corporation, an industrial minerals company engaged in the mining, processing, and marketing of perlite. Located in Lake County, Oregon, it serves customers throughout the West, Midwest, Canada, Mexico, South Korea and Australia. Its assets consist of an 800 acre mine which contains the Tucker Hill perlite deposit, the processing facility in Lakeview, and the trans-loading terminal near Klamath Falls, Oregon.

Perlite is a naturally occurring volcanic glass that contains between 2 and 5 percent water in the glass structure. When subjected to heat, the perlite will expand up to 20 times its original volume. The expansion is due to a change in state of the water found within the structure of the rock. The physical properties of the lightweight expanded perlite give this product unique commercial value for building construction, horticulture, and industrial uses.

Mick Stanley, president and chief operating officer of Cornerstone Industrial Minerals Corporation, remarked, "Perlite is a phenomenal product with a broad spectrum of uses. When we were looking for financial assistance to expand, we knew we needed an exceptional bank that would listen to our unique needs and would not try to place us in a cookie-cutter category."

He continued, "We are pleased to partner with Plumas Bank. Although we're 56 miles away from a Plumas Bank office, Remote Deposit makes it very convenient to bank with Plumas Bank. The loan team is very responsive and professional. We've been able to enhance our business and increase our efficiencies by modernizing our outdated equipment fleet; thereby, reducing our down time and maintenance cost."

Stanley concluded, "Quality is key in our business; the quality of our ore is sought out by customers from west to east, demonstrated by our newest client in Lawrence, Massachusetts. The quality of our perlite outweighs our client's additional transportation costs. Likewise, today's technology has made it possible for us to choose a bank based on quality, not distance. Plumas Bank is our bank of choice for a variety of reasons."

About the companies:

Cornerstone Industrial Minerals Corporation: Cornerstone Industrial Minerals Corporation is an industrial minerals company engaged in the mining, processing, and marketing of perlite. Located in Lake County, Oregon it serves customers throughout the West, Midwest, Canada, Mexico, South Korea and Australia. Its assets consist of an 800 acre mine which contains the Tucker Hill perlite deposit, the processing facility in Lakeview, and the trans-loading terminal near Klamath Falls, Oregon. For more information on Cornerstone Industrial Minerals Corporation, visit [ www.cornerstonemineral.com ].

Plumas Bank: Founded in 1980, Plumas Bank is a locally owned and managed full-service community bank based in Northeastern California. The Bank operates eleven branches located in the counties of Plumas, Lassen, Placer, Nevada, Modoc and Shasta. Plumas Bank offers a wide range of financial and investment services to consumers and businesses and has received nationwide Preferred Lender status with the United States Small Business Administration. For more information on Plumas Bancorp and Plumas Bank, please visit our website at [ https://plumasbank.com/index.html ].