Dave,
As you say, this is an intriguing line of discussion. In the
small number of bone burning experiments I have done, it doesn't take a
high temperature to calcine bone--less than 500 degrees C for one hour.
Most campfires are hotter than that. Bones placed at the bottom of a wood
fire are extremely calcined, cracked, and brittle. Unless a bone fire burns at
very low temperatures, it is highly likely that fuel bone would be very
calcined, cracked, and fragmented. It would also be interesting to know
if the bones could sustain a fire once the oil/organics burned
out of the bone. At that point, they are predominantly inorganic.
Another thought is that another kind of
non-charcoal producing fuel might have been used, i.e. dried grass, animal
dung, etc, in conjunction with the bone. Was there a lot of ash in the
firepits? I've seen firepits with lots of ash and little charcoal. Whether wood charcoal was reduced
to ash in an intensely hot, length fire, or a different fuel was used,
would be interesting to know.
Susan
--Mistakes are the Portals of Discovery (james joyce)
Susan S. Hughes
Dept. of Anthropology
Box 353100
University of Washington
Seattle, WA 98195
On Wed, 11 Jul 2001, Dave Maxwell wrote:
> This is a very intriguing line of discussion. I have been working on
> materials from San Nicolas Island (off southern California, about 100 miles
> SW of Santa Cruz Island, mentioned by Roger Colton) for some time. SNI has
> very little vegetation, due to an average rainfall of about 4 inches. We
> have recovered the remains of several features identified as hearths, all
> virtually devoid of charcoal (burned bone is rare in most). We also have
> another feature, a burned pit, that is full of bone most of which is burned.
> I've been wondering for some time what was used as fuel, given the lack of
> vegetation, and have toyed with the idea that bone and grease (possibly from
> fish?) were used in some combination; unfortunately, I have not had a chance
> to test this. Two Questions:
> 1. Does anyone know what kind of destruction you see on bone burned as
> fuel? I would assume it would be highly calcined, but this is only a guess.
> 2. Does anyone know whether there is sufficient grease in fish oil to use
> as a source of fuel? Obviously this will vary by species, but I'm wondering
> on a general level.
>
> Lots to think about with this topic.
>
> Dave Maxwell
> Statistical Research, Inc.
> Burnaby, British Columbia
>
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