Gray sandstone block Sandstone is a sedimentary rock composed of rounded grains of quartz bound together by sillica or lime.the sandstone deposits are found mainly in Rajasthan,Shandong province is one of the areas in China with extensive sandstone deposits. 1)Finished:honed,flamed,bush-hammered ,polished, fine picked 2)Color:red,grey,yellow,green,white and other popular colors 3)Reasonable price with excellent service and quality