I helped out a friends of myselfs neighboor this week with dropping off some stone and raking it fairly level for him to screed and compact himself. When I was there talking to him last week I thought that he was discribing stone dust as what he wanted for his base material to be put down on top of geofabric. This guy has a VERY strong Chezk accent. So Yesterday I went and got 3.5 tons and spread it in the area for his new patio. Well I called him today and left a message asking how it was. He called me back tonight and said that he was thinking that I was going to bring in 21A for the base then he would set in 2 inches of concrete sand for the paver bed. Well I was at a class today and learned that 1 inch of sand is all that is needed now adays. But his and my question is will the stone dust be sufficent for a base material or should it be redone with 21A material. I had talked to my stone supplier last year about this and thought that I remembered them saying to use the stone dust as base material. Oh yeah the patio is 13' X 16'. Thanks guys.