CompuServe Messages

John, I picked up (no pun) most of the dental tools from my dentist. For free. HOwever, with recent OSHA regs on blood-borne pathogens (Nathan I'm not making this one up) most dentists have gone to autoclavable pieces or they dispose of used equipment in a manner used for needles in the past. My supply of dental burrs for the Foredom dried up overnight as a result. The Foredom was purchased in Quartzsite at the POWWOW in '89 for about 150 bucks. Acid prep of calcerous specimens requires hydrofluoric acid as it does not attack apatite or calcite. Acetic acid (or vinegar) will rapidly fizz them away. Same for hydrochloric, sulfuric and nitric. ********DANGER******* DO NOT USE Hydrofluoric Acid UNLESS YOU HAVE BEEN PROPERLY TRAINED, HAVE PROPEREPROTECTIVE EQUIPMENT AND EXCELLENT VENTILATION. HF Acid causes the worst chemical burns of the common strong acids. It is attracted to Ca++ ions, hence the bone. Untreated burns result in severe hypo- calcemia and can result in death. Treatment requires the use of calcium gluconate solutions or quaternary amines provided by your friendly BURN CENTER. ********END Message**** NOw back to our regularly scheduled message- Acetic acid (10%) 1 part glacial acetic in 9 parts water is usually mild enough for loosening matrix around non-calcerous fossils, particularly good when the fossils are silicaceous replacements. Vinegar is usually 4-5% and can work as well. Hydrochloric acid (HCl) can work at the same concentrations but tends to be a bit more vigorous. Oxalic acid works ok for removing iron stains on many items. I haven't tested it on calcitic fossils though. One reference for fossil prep techniques is: Fossil Animal Remains by A.E. Rixon ISBN 0 485 12028 3 Another I haven't tracked down yet: Paleotechniques Pub. by Dept of Geological Sciences University of Tennessee $20.00 In addition, a forum member, Jerry Harris is a preparator for the Denver Museum of Natural History. His ppn# is 731132,3372. I will happily lend any advice you might want that I have, Michael