You can see some of the older (up to about 1895 or so) Sheffield "exhibition" quality knives with truly drop-dead stag - and much of this has a super-fine patterning. I speculate that it came from a sub-species or isolated population of sambar deer that were long gone by 1900 or so.
Here is a knife from the J Greenhough Sheffield exhibition knives collection:
This is the sort of thing I think they were trying to recapture.