Bear in mind, 'Stag' Antler is true Bone...
And very nice 'smooth' Bone Stocks can be fashioned from it, when one has sections with sufficiently thick outer layers.
These, while a different look from Ivory, if Bleached and Polished right, are very 'white', and very fine grain, and very good looking...and offer a very positive grip.
When one sees Anique Grips/Stocks on Pistols, said to be 'Bone'...probably, usully, it is Stag Antler, filed or sanded down past the outer irregularities, and polished.