Our History

Our Commitment to You.

From 1957 to Now.

P.W. Gillibrand is committed to being the Specialty Aggregate Products “Supplier of Choice” in the Western United States.


We provide quality products, excellent service, leading technology and added value in meeting and exceeding customer expectations.  


We provide a safe workplace, respect for the environment and act with integrity towards our employees, customers and community.

P.W. Gillibrand is the legacy of founder Phillip Walton Gillibrand. Phil started as a miner’s son and worked his way up to becoming the sole owner of his own company.

His grandfather left England in 1885 to settle in Lancaster, CA. After a brief stay, the family moved to Tapo Canyon in Simi Valley, CA. Phil was raised in Simi Valley and lived in the community his entire life. He married at age 18 and was holding down two jobs to make ends meet.


During the day, he paved driveways and delivered gravel to local farmers for use in road construction. In the evenings, he worked at what is now the Boeing Rocketdyne facility in Chatsworth, CA.


In 1957, he founded the P.W. Gillibrand Co. He left Rocketdyne in 1959 and devoted his full attention to the growth of his young business.

“If you would have told me how big the company would become when I just started out, I would have told you you’re crazy.”

Having seen a need for construction aggregate, he acquired land near his home in Tapo Canyon and began mining and processing rock, sand and gravel to supply the growing construction industry.


In the late 1970s, the company added high quality industrial sand to its product line. Today, in addition to construction aggregate products, the company is a leading producer of industrial and recreational sand products in the Western U.S.


He was a very charismatic man and always on a first-name basis with his employees. He was very much a believer in treating others as you would wish to be treated.

“If you consider my business a success, it isn’t just me; it’s all the wonderful people who work for me.”

Phil passed away in March of 1999 and the company continues under the leadership of his wife Celine and grandson Brandon Theising.

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If you have questions or would like to place an order,

contact us today.


Information Forms

Safety Data Sheets


Film Locations

Contact Us

Order Information

P.W. Gillibrand Products
844-4MY-SAND (844-469-7263)


Riverside Milling Products

Corporate Office

4537 Ish Drive
Simi Valley, CA 93063

Bakersfield Location

9952 Enos Ln.

Shafter, CA 93263

Brady Location

1000 Oglebay Norton Dr.
Brady, TX 76825

Riverside Location

2157 Avalon Street
Jurupa Valley, CA 92509

San Juan Capistrano Location

31302 Ortega Highway
San Juan Capistrano, CA 92693

Simi Valley Location

5810 Bennett Rd.
Simi Valley, CA 93062

© Copyright 2019 P. W. Gillibrand, Co. All rights reserved. Website developed and maintained by Pinto Productions.