G'day WS,
Is indeed a natural edge bottle stopper. What you have there is the outer skin of the burl (top part) not bark! Natural edge is called on turnings where one or both of these are part of the piece, normally the outer edges or the further edges from the center piece, if you know what I mean...!
The effect is quite interesting as in the decorative aspect but I have always believed and preferred bottle stoppers with a smooth surface of the top part. This is mainly due to the fact that, the part of the hand used to insert the stopper is the palm of the hand (normally) which is pressing the stopper from the top in a down or twisting motion so, sharp end stoppers will probably be a bit of a painful exercise for those inserting it, not forgetting those that use the "magic" final touch of a nice "tap" with the palm of the end on the stopper top to make the final seal stage!:biggrin:
This doesn't mean that your idea and execution aren't good, indeed if bottle stoppers weren't made for actual "use", as a decorative piece, that would work really well.:wink:
Cheers
George