Some weeks back I asked about using granite or marble for a bathroom windowsill. I checked out a few places and found a nice piece of marble and that will be what goes in. It is cut to 10.75 x 54. Polished and a bull nose edge Looks great and will match the wall tile, mostly white with a little gray streak.
I paid $310 for it. Seems to be about right from other prices I got for other materials. A man made product would have been $300 from a kitchen store.