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Degreasing can be tricky. The absolute best way is with a commercial degreaser, or other solvent. Automobile lacquer thinner works better than anything else I've ever used. But of course there are issues with health effects of sovlents and the need for adequate ventilation that have to be addressed. Other than that, water maceration aided by ammonia seems to work the best. Here also there are drawbacks - you have to get all the ammonia out of the bones before they dry, so repeated soakings and changes with fresh water are needed, which can be a bit wasteful of water. It is important, in my view, to avoid getting all the grease out of the bone. A small amount of grease keeps the bone from becoming overly brittle and cracking. It also makes photographing the bones much easier. Pure white bones, particularly if you commit the sin of bleaching them (even with H2O3) are so brilliantly white that surface features become hard to even see, let alone photograph, and you end up having to soak the bones in tea to get good pictures. I've never found the drilling technique very helpful, but some of the old time preparators always used it, especially for large mammals. Helmet Fuchs at the AMNH always drilled the long bones. H. Chubb never did, other than for mounting purposes. Rich Richard S. White International Wildlife Museum Tucson, AZ 85745 In a message dated 7/18/2012 7:16:37 A.M. US Mountain Standard Time, [log in to unmask] writes: Pam, yes, I've seen the drilling technique used by Angelos used successfully. Sometimes the holes are placed vertically, by drilling straight into the ends of the bone parallel to the shaft. This is generally done because the skeleton is intended for mounting and this hides the blemish. But Angelos is right that it would be better to avoid the trabecular and/or spongy bone that lies at the ends. One does note that when a long bone such as a tibia seems hard to de-grease, the greasy areas tend to not be toward the center of the shafts, but rather at the ends of the bone, as if the fatty marrow had indeed been mobilized by the usual simmering in water, and had flowed out toward the ends of the bone, but then had been unable to find an efficient way out. I am afraid that the only technique I've ever used to mobilize the grease is to simmer the bones in water. I do try to avoid outright rolling boil, as especially with the smaller elements or with flat elements can produce warping or even decalcification. I don't think that drying the bone, i.e. placing it in front of a heater or out in the California sunshine would do much, at least not in any reasonable amount of time. When we pick up bones lying out on top of a field someplace which Mother Nature has been working on, almost always they have been lying out in sunshine and rain for at least a year if not more. -- Deb Bennett >