Interesting thread, humorous, even...so, in that vein (oops!), I offer the following: Petoskey stones polish up real nice. They are not suitable for construction, but they are real popular in northern Michigan, found on the lake shore near Petoskey. We polished a few to use as cabinet pulls, but that was as close to construction use as I've seen. Purchasing them is pretty much limited to gift shops in the Petoskey area of Michigan's northern lower peninsula. Petoskey stones, to the uninitiated, are actually fossilized coral, Hexagonaria percarinata. The stones were formed as a result of glaciation, in which sheets of ice plucked stones from the bedrock, grinding off their rough edges and depositing them in the northwestern portion of Michigan's lower peninsula. Ilene R. Tyler, FAIA QUINN EVANS | ARCHITECTS 219 1/2 N. Main Street Ann Arbor, MI 48104 ph: 734 663-5888 fx: 734 663-5044 -- To terminate puerile preservation prattling among pals and the uncoffee-ed, or to change your settings, go to: <http://listserv.icors.org/archives/bullamanka-pinheads.html>