I might make it also count as cold-iron and/or silver and/or byeshk(or however you spell that stuff from Eberon)... or just short-cut it all and say it counts as any material worth 1000 gp per pound or less for those purposes.

Would go very well for a necromancer who likes making my Empty Skins (see my Full List of Homebrew AKA extended signature, listed in my sig).

The utility is so narrow (it doesn't even help with harvesting anything other than the skin) that I would count it as a +2 weapon cost-wise.