Here’s a site that just sucked down a couple of hours. The main thing I learned is that if you’re going to face a wall with sandstone, use a deep roof overhang. Some of the limestones and marbles look pretty iffy too. Of all the granite samples I looked at, only one showed any visible weathering. Kind of odd to see a granite block looking like it was just put there, next to a sandstone block that looks likes it’s been shot out.

http://stonewall.nist.gov/