Dip test?
That's fishy...I work in the foundry industry and anything with moisture in it WILL EXPLODE if dipped in molten metal.
I know of foundries that have EMPTIED 2 ton crucibles because some guy dropped a wooden handled hammer into the melt.
I haven't heard anyone mention the obvious, but cotton and wool both will not melt, nor burn freely, and are much cheaper any easier to find than exotic safety materials.
