A light weight translucent horn growing from a crystal and filigree base. It's hard to make a horn that sprouts from your forehead look elegant but if you make it look more like jewelry I think it works!
What did you make the actual horn with, blown glass? It looks like an icicle. Very cool. I've been trying to find or make a horn that balances well on a human head for years. It's really hard. All the fabric ones, even if you avoid colors and decorations that make them look cartoony, end up too bulky (fat in circumference). Scultped out of materials I can get my hands on, they either end up too heavy for anything but anchored to a reinforced full-mask, or again looking obviously fake.
It's not just that you've make the horn look elegant that's an acheivement, it's that it balances with the rest of the face and head. It looks plausible that the horn belongs there.