Thanks for asking! These blue stone tiles are sitting on pedestal pavers on this roof top. The short answer is yes, you could use this system over a concrete patio. The bigger issue would be how you are going to create edging as well as how you want to handle the height from the pedestals.
If you're asking about laying just the stone over concrete, best practice (at least in Chicago) is to remove the concrete and lay the stone properly over a compacted base.
Hope this helps. Let us know if you have any follow up questions.
Topiarius, Inc