To: E. Charters who wrote (17775 ) 8/8/2006 2:58:41 AM From: marcos Read Replies (2) | Respond to of 78412 Hi EC, remember i asked you about black rocks and you suggested using a magnet to determine magnetite, well thanks for that, i finally found one today that was weakly magnetic ... wasn't one of the rocks i was thinking of though, not from this property, but one i brought in from elsewhere, no idea where, i used to toss a few good looking rocks in the pickup when building road or logging, always had the plan to do the stonework i'm starting now You have to wirebrush the rocks clean so the cement sticks nice, so you get a good look at all sides of each one, rolling it around in the wheelbarrow under a running hose ... the diversity is incredible, so many different kinds of rock ... one kind i had lots of because it tends to have a nice shape for building, is no good because it's made of clay or something, you brush it and the surface turns to grease, makes a milky cloud in the water ... too soft, don't trust it, feels like it'll melt, i'm guessing some form of shale ... another kind, harder but still will make that milky cloud if you brush hard, is quite greenish, so having heard of greenstone belts i'm assuming this is the stuff ... this all comes from glacial till, when i dug the pond here the bottom six feet or so of digging were clearly imported fill from somewhere, all mixed up with a cream-coloured sandy clay ... with snail shells in it, lots of them, some ancient marine animal Anyway it's made geology real to me, and interesting ... always before avoided learning much in that regard, partly on the theory that a little knowledge is a dangerous thing, also on conviction that it was share structure and seasonality and promo that counted, and all the rest distraction [Elvis never wrote a single song, but he had a hundred Cadillacs]