Now for a sloped mortar bed to the shower drain.Topped with a waterproofing membrane. Add some basalt stone mosaic tiles plus a few agates and shells. Now fill it in with grout.  Then wipe off the excess.  Et Voila!  It’s a bit darker than we had planned but it turned out pretty cool.  We will have more stone going up the back and side walls and tile matching the rest in the master bathroom on the other walls. (not visible in these pictures)