You might try pencil lead to put a hole in molten silver.
This is off-topic, but this comment reminded me of something, sorry
about the interruption.
Have you ever watched those PBS programs about volcano’s in Hawaii
where they show people dipping into the molten lava to measure the
temperature or whatever they do? Every time I see that I think,
wouldn’t it be cool to take molds out there and cast sculptures with
molten lava? It would be hot, but I bet it could be done.