I've purchased from a shop just up the coast (OBX) and had mixed results. I've got a few large pieces (2' across, trunk shaped) that have been in my garden for several years. Hacked off a piece, boiled it, mounted it on some slate and it was fine. Did not get soft, few tannins if any. I eventually sold it when I changed my scape.
I also picked up some interesting smaller pieces from the "dollar bin". IMO these pieces would have been better suited for a terrarium or reptile cage. After boiling they still released a lot of tannins. They would not sink so I threw them into a small pond out back. It took 8+ months before they sank. After reboiling to remove the algae and whatnot, they wood was a bit soft. When I dried it, there was a brown powdery residue on the surface (similar to charred wood).
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