Are you looking for something to stack for a retaining wall kinda thing, or something to walk on or just decorations?
Up in the NE/NW around the Panorama Hills area it's very rocky. Sandstone kinda rocks alot of them have fossles of shells and asorted creatures in them. In my last three houses I've gone there to get a bunch of them for my garden and flower beds. You have to search through the piles but they are very flat and can easily be shaped with a hammer. For a flower bed they are perfect, I'm not sure how they would stand up to walking on constantly in a patio situation.
Best thing is they are Free, and come from the area so look very "natural"... I'll see if I can find a picture to post.
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