I frequently purchase scraps of solid wood flooring from the Habitat for Humanity Restore to use inb making toys, etc. Generally, the wood is easily identifiable, but I recently picked up a piece of a very hard, very heavy wood. It is a dark brown, stringy like black palm, but with smaller strands. even when using really sharp tools, it is hard to turn. The unusual part is that when turning, although the wood is dark brown, a very fine chrome yellow dust is created when I turn it. I thought this might be the result of the hard finish put on the flooring, but I get the dust when facing the back side as well as the front, and even when drilling the wood. I hope this is enough information for someone to identify this mystery wood. thanks for any suggestions.