I got a call from a friend whose tree lost a few large branches last week. It is Russian olivewood. He brought me a couple of pieces two days ago, and the rest will follow shortly.
The sapwood is very light yellow, almost white, and the heartwood is a deep chocolate brown. The grain is very dense and tight, and the wood is heavy. I can clearly see myself cutting slices out of the small branches to make pendants or parts of necklaces. The picture below has two dry pieces and a wet one.