CompuServe Messages

Steve: I am not a 'field' geologist (i.e. outdoor-type), but if in fact you are seeing quartz grains of sand-size <<several hundred per square inch!>>, I will hazard to say it is probably sandstone. An igneous rock in contact with limestone would (probably) not have suddenly appeared but would have had some boundary-change marked by yet-another kind of rock. Limestone itself can be granular — in the extreme this is called marble — but the change in character you describe supports the above. If you think it's important, you can drop a little dilute muriatic acid (hydrochloric acid — 5% in water is strong enough) on it to exclude this possibility. Limestone will fizz. If only the matrix and not the grains themselves fizz, you *can* have sandstone with limey cement. I'm sure it is possible to split sandstone with explosives, probably just a different technique (deeper/narrower/shallower/bigger plug holes, something). But I have no experience in that; maybe you can find someone who does (once you confirm the identity of the rock). >> is it wide spread or will I run out of it!!! No way I (or anyone, with no more data) can tell the answer to that. I would ask around — any old-timers who might have dug wells in the area, near-by colleges with earth science programs or geological formation maps. While you're at it, take a piece of the rock to the college, or even a high school science teacher, for identification. And try the "ask a geologist" service Doug recommended. For that, it will help if you can get a topographic map of the area and pinpoint your location on it. Sporting goods or hunting stores will sometimes have those maps. Good luck. — E.