With shale gas, it is a mixture of clay, rock and quarts and calcite. To produce these things artificially, we only need to produce the calcite, as the others would come from natural grades of rock, sand and soil, with the quartz being a by product of melting sand in a bot, where the silicone bleeds off to produce silicone and quartz, where the silicone goes to the top of the liquid, and, the quartz to the bottom, of course.
Now, the calcite, that is where we have bone mixed with rock, yes? This could be realized by combining sand and bone, or, as another source of better calcium, that is hydrated, 'milk,' but, if that fails, sap from a tree, yes?
There we go, shale gas production!