I am fortunate to have the experience of seeing wood cut fresh from the tree. Having a sawmill, I get to open a log for the first time. It's incredible the changes that occur over a period of several minutes. Walnut is green & vivid, steadily darkening to it's normal dull chocolate brown that we all know walnut to be. When first cut, it's as beautiful as anything. Same with piss elm. It's a crimson red/orange that seems like it should burn if you touch it, but within days it turns to a pale grey/brown. I have cut oak that looked black & purple, but it doesn't last, soon turning to common oak brown. No wood gets better with age. They're all most beautiful immediately after the first cut. The only exception would be spalted stuff.