Could someone please let me know what 4 inch minus rock means. How small can the rock be and what percentage of this 4 inch minus should be 4 inches and what percentage could be 3/4 inch or smaller. I had my backyard landscaped and the quote is for 4 inch minus river rock to cover the drainage swell. The contractor brought mostly 3/4 inch rock and just a little bit of 4 inch rock. When I complained about the size of the rocks, he said that 4 inch minus could go down to pea size and as long as there are a few 4 inch pieces that he is complying with his quote. Is this true? I'd really appreciate a response.