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Author Topic: How do cremated bones differ from buried remains?  (Read 10351 times)

Offline aok

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Hello...

I'm wondering if ashes from bones that were buried are the same as ashes from bones that were cremated. And I'm referring to the same human or animal specimen. In other words, if a human or animal was buried and turned to ashes VERSUS a human or animal that was cremated and then ground into ashes --would the ashes from both scenarios wind up being the same -chemically, physically or otherwise.

Thanks



Mod edit - formatted subject as a question - please do this to help keep the forum tidy and easier to navigate. Thanks.
« Last Edit: 19/01/2011 11:34:01 by BenV »


 

Offline CliffordK

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Re: How do cremated bones differ from buried remains?
« Reply #1 on: 14/01/2011 21:43:55 »
Interesting question.
Obviously the remains from decomposition aren't called ashes (are they?)

But, is there a difference between natural decomposition, and cremation followed by natural decomposition.

The cremation process would drive off the water, and burn up the hydrocarbons.  Calcium compounds, phosphates, and other minerals would be mostly left behind, although some may escape in the smoke.  They may not oxidise.

The bone and calcium tend to be the most resilient, but technically everything can be bio-absorbed.  In decomposition, the first things to go would be the hydrocarbons, and perhaps the phosphates, leaving the teeth and bone for later.

So...  there may not be any difference.

Perhaps it would depend on how the remains are treated.

In some places, bodies are buried in a manner that inhibits decomposition.  Concrete casks, very deep in the soil.  While not "sterile", embalming may have the effect of slowing decomposition.

Cremation ashes, however, are considered sterile (not good to start decomposition), however, being sterile, they are not required to be buried 6 feet under.  They are also in small pieces that could improve the bioavailability, except that they are also much more concentrated when left together.  Anyway, so spreading out the ashes at nor near the surface of the earth will likely speed up decomposition.  The oceanic environment may also speed decomposition.

Did this answer the question?

The minerals are the same whether burnt or buried.
The oxidation state is probably not important for the minerals, and may not be changed with cremation.
The speed of decomposition (and what is decomposed when) may be different between the two, but would also depend on things such as embalming, and how the body is buried, as well as whether or not the ashes are scattered or buried in a lump.
 

Offline aok

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Re: How do cremated bones differ from buried remains?
« Reply #2 on: 16/01/2011 23:35:16 »
Thanks, Clifford. Great answer. Couple questions...

"Cremation ashes, however, are considered sterile (not good to start decomposition)..."

1. What do you mean "not good to start decomposition"?
2. If the cremation remains are not scattered but put into an urn, are they still the same as the decomposed buried remains?
3. Do all the bones decay? I read, in Jewish literature (not science) that the coccyx bone or one of the bones in the neck (not sure which) never decays --unless cremated. Is this true?

Thanks
 

Offline CliffordK

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Re: How do cremated bones differ from buried remains?
« Reply #3 on: 17/01/2011 07:26:07 »
Decomposition would involve both organic and inorganic processes. 

Your gut, for example is full of bacteria, kept in check by biologic processes.  Once one dies, these start growing quickly, which is one of the reasons bodies will generally float a couple of days after death.  The number of bacteria outside the skin and GI tract, of course, is small, but they spread quickly.

It may be more of an inorganic leaching that affects the bones, I'm not sure.

Your Urn will be more or less sterile and dry (free of water).  No hydrocarbons.  I.E.  It is not a good environment for bugs to survive in.  If kept protected from the elements, it should last forever.  You could add some HCl to them and they would mostly disintegrate in a few days.

Mummification, of course, would be a process of slowly drying out the body (or in some cases, bodies have been frozen for thousands of years).  If dried, and kept dry, the body could also last for a long time.

In a more natural environment, our teeth will probably out last other bones in a natural environment.

Reading about Stonehenge, apparently there were human graves associated with the construction.  Some of the burial sites are now being analysed with many bone fragments remaining.

Animals, of course, die all the time.  One rarely encounters small animal remains older than a year old or so, nor do you frequently encounter large animal remains more than a couple of years old.  I would consider that an indication of how quickly they are reabsorbed into the environment.  Think of what the world would be like if every dead insect and animal just laid where it died.   [xx(] 

Calcium, and other minerals are vital for life.

Anyway, left to nature, the ashes or the buried body will end up the same. 

BTW:
There have been some new methods discussed.
Crymotation & Resmomation

http://news.bbc.co.uk/local/cambridgeshire/hi/people_and_places/newsid_9344000/9344975.stm

 

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Re: How do cremated bones differ from buried remains?
« Reply #3 on: 17/01/2011 07:26:07 »

 

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