.:::More Combat Less Cosmetic:::.

[Jetstream_Fox]

This already happens very commonly... Crawler Silk/Chimera Manes comes to mind. And literally anything for leatherworker.

I'm pretty sure those items aren't special at all, I'm almost certain they're common hence the reason they drop from mobs. I think OP wants actual rare item drops from mobs, like how Diablo 3 killing an Elite can drop high end craft items.