I was always excited when I walked past young American chestnut trees on the Appalachian Trail. They may be struggling, but they're still there!

I really like the bubbles in the pewter - like you said, they mirror the wormholes in the wood. If you'd like to avoid the bubbles next time, try pouring the pewter from higher up, so it agitates itself in the mold and settles in all the crevasses. Or, after pouring the metal, give the knife a good shake (wearing heat-proof gloves!) to settle out the bubbles.

Andrew.