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Fossilized Burnt Wood?

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pete:
Hi
I pulled this rock from my garden bed collection the other week because of the black colour. When I looked closely it looked like fossilized wood with some silicified veins but black.
I cut a couple of slabs and the black went almost to the centre where it became a dirty brown colour. I cabbed a bit also and it gave a very pungent odour and very dirty blackish brown swarf.
I think it might be burnt timber or almost charcoal prior to fossilization.
It's origin is somewhere in Australia.
Is this possible? What else could it be? Any ideas?

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fossickeract:
 Reckon yu spot on Pete, quite common in Kangaroo Valley, South Coast NSW. Often there the closer yu get to the site of the volcanic intrusion the more the wood has been burnt which makes sense. Takes a good polish, looks good with veins of bluish common opal but bit ordinary in plain blacks and browns.
                                    beers Ted

pete:
Thanks Ted.
I was thinking along the lines of a bushfire but a volcano makes more sense. And I thought it was like opal the veins running through it though of course not precious opal. But those veins seem to be mostly confined to the surface. You're right, the dense parts certainly take a nice polish.
It's really interesting the origin of these sorts of things.
 beers
Pete

llarson:
    We find the same sort of stuff  on the Oregon coast, the surroundings being clay remnant of volcanic ash, and ancient lava flows. It polishes about like yours, some very nicely, and some about as well as a brick.

bjhodgkin:
We get some similar material up in the Hunter Valley at a gravel/conglomerate quarry. The outside layer of some bits still looks and feels like charcoal. I wasn't sure if some of the wood had began to turn into coal or if it had been burnt before being washed down the river that it was deposited in - it is fairly close to a couple of good sized coal holes.

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