Has anyone heard of or tried Aero Marine 320/21 Epoxy Resin for sealing wood?

It was suggested to me for sealing a piece of wood  that has a very rough, craggy surface to it.

Turning the piece as a natural edge bowl would have this very craggy edge to it and my imagination can already picture it but I agree that it will probably need to be stabilized before turning.

Any other ideas??

Are you wanting a smooth surface or simply wanting a coat of something on the rough surface?  If the latter, dewaxed shellac, Danish oil, wiping varnish, and many other products would leave a thin coat on the rough surface.  I've made several natural edge black walnut bowls finished with wiping varnish - before rubbing another coat on the inside and outside using a corner of my rag I'll put a coat on all the bark.

Now I understand.

After reading the suggestion here, when making once turned natural edge bowls, as soon as the outside shape is finished I drizzle thin CA on the surface of the bark and on the exposed outside edge, and repeat.  I will try to keep turning the bowl blank so that the CA on the exposed outside edge does not run down onto the outside surface of the wood itself and stain.  As soon as the inside edge of the rim is finished I drizzle two coats on that surface as well, again trying not to get CA on the inside surface of wood.

I use alkyd varnish as a wiping varnish, and it darkens the bark just as the CA does, so the CA on the top and sides of the bark does not stand out under the finish.  You might want to experiment first using some CA on scrap wood and applying your intended finish to see how the combination looks.