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
>
> Hi Pam,
> If you are not too strict about sacrificing a tiny portion of each long
> bone, a good way to get rid of that grease is to drill two small holes
> (5-10 mm should do) per long bone. When I had this problem, I drilled one
> hole near the proximal end (go for the area where the hollow part of the
> shaft starts, i.e. avoid drilling a hole into spongy bone) and one near
> the distal end (with the same logic). I do not know whether the following
> enhanced degreasing but I drilled one hole on the anterior side and the
> other on the posterior (with the possibly erroneous assumption that an
> 'S'-shaped current would flush out grease more efficiently).
> All the best,
> Angelos
> Date: Wed, 18 Jul 2012 06:48:38 -0400
> From: [log in to unmask]
> Subject: Re: [ZOOARCH] bone degreasing problems...
> To: [log in to unmask]
>
>
>
>
>
>
> Thanks for the photoshop advice, Deb!
>
> On another vein, I understand you've done a bit of skeletal
> processing...
>
> This subject has come up a few times and I've read various...but...
> I've got a collection of Equine material which I've been processing with
> defleshing, dermestids and biotex soaking. They're fine, clean, etc. but
> still
> VERY greasy...been drying a set in a low oven for some weeks and have some
> drainage but not much.
>
> Environmentally, I'm in Britain, so drying outside is not really an
> option.
>
> These are obviously modern specimens and robust, still I'd rather avoid
> significant damage to the cortical bone...but I'd also really like to
> decrease
> that fat content. Suggestions?
>
> Considering burying some in salt...
>
> Pam
>
> Pamela J
> Cross
> PhD researcher, Bioarchaeology
> Horses of Men & Gods
> project
> (AHRC, NT, SHS, Bernard Cornwell & MoL)
> Archaeological
> Sciences, University of Bradford, BD7 1DP UK
> p.j.cross (at)
> student.bradford.ac.uk / pajx (at)
> aol.com
> http://www.barc.brad.ac.uk/resstud_Cross.php
> http://bradford.academia.edu/PamCross
> http://www.suttonhoo.org/saxon.asp
> (2012, Issue 54)
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