Thanks for stopping by, Nemoman, Beth, and...
Hanter, I have a thread in "other FS" on the FWI. Apparently the good stuff is the outer layer of the tusk. The density needs to be uniform, of course. Here:
https://www.acousticguitarforum.com/...d.php?t=583885
The consensus seems to be it is much the same as fine elephant ivory which is seriously restricted, and was the Saddle of choice for most all the super vintage instruments from the pre war era.
I invested in Bob Colosi Hard West African Ivory Nut, Saddle and pins for my 2011 RT2c custom. (Now can not be shipped most states) When I swapped them in I do believe the sound got a bit more distinct and a tad bigger. It COULD be placebo effect. But I don't think so!
Perhaps John will give us the benefit of his experience here... hint hint!
Stay well and play pretty!!!
Paul