Picked up some new substrate (thanks Keep)  Its more along the lines of T grade 3M but much cleaner to rinse  Marbles have been on it now for 2 weeks and maintained their color and havent darkened at all.  I am wondering if part of it isn't the Halide lighting vs conventional flourescent.   Anyways showing of a few pics of the substrate plus an excuse to squeeze in a couple of my rays.







				
			





