Boudica
I'm here for Educational Purposes
Even then, That stone was extracted from the earth....You won't find "environmentally friendly" vinyl any more than you'll find environmentally friendly gasoline. Petroleum products leave a definite foot print from the moment the crude is sucked from the earth until it exits the tail pipe...or is tossed into the land fill.
About the "greenest" option you'll find is hammer and a chisel and stone.
JB