pinecones
Hi Jason,
I use West Systems epoxy, resin #105 with the slow hardener to fill the voids and the fast hardener for the finish. Lot's of CA along the way. There are lot's of ways to go, however, with various hardeners and fillers, but don't bother with polyesters - they don't have the adhesion. Pinecones material varies from very hard to very soft, and there are hard glossy surfaces inside that do not take very well to adhesives.
I use monterey pines and coulter pines - these have the stem growing in on an angle into the cone which produces the starburst in the side of the vase. They are turned to thumbnail thickness for light weight and translucence.
Mike