The Flying Dutchman Medal is made from lead-free pewter, and cast using the ancient "lost wax" method. Bilgemunky remembered reading about the technique in a history book, and figured, "gee, cave men did it. How hard can it be?" (forgetting that cave men also wrestled sabertooth tigers.)
Actually, it wasn't that difficult - although very tricky. Much wax, plaster paris, and pewter was ruined before satisfactory results were finally achieved. The end product was a truly one-of-a-kind medallion featuring Bilgemunky's own jolly roger, depicting a skull with crossed swords above a crown.