Tri-statematerials.com is the on-line home of Tri-State Materials, located near Diamond Valley Lake, in Winchester California. Tri-State Materials offers a large selection of products ranging from decomposed granites, cobbles, and boulders, to flagstones and other exotic specimens. You can check out several of our products on our product page. Just click on them and learn more about each type of material. Be sure to check the Frequently Asked Questions (FAQ) page for any questions you might have, or feel free to contact us withany questions not answered or clearly detailed on the site.