Wire is used in jewelry for wrapping stones, stringing beads, and creating bent wire creations among other things. (I'm not really a wire person..... all thumbs!) It can be used for those purposes in metal clay also, but it can be used as a tool.
My last couple pair of earrings were made by bending 14 Ga. copper wire into a design, flattening it with the chasing hammer and rolling clay over it to make an impression. (This technique can also be used to create a design for the copper/bronze inlay technique which I wrote about in an earlier post.) It's great for earrings as the wire can be flipped for the second earring to create a mirror image.
Another technique involves bending the wire into a three dimensional form and draping the clay over it. After drying, the wire is removed and the open side is inclosed with a slab of clay. It's a little difficult to control what the finished form will look like. (At least I found it difficult.)
The two pieces shown here are both in the greenware state (dried but not fired.) They also haven't told me yet what they want to look like when they're done. (Remember my jewelry talks to me!) That's why they look a little strange yet. I drilled three holes into the bigger piece, intending to put copper, bronze and silver rods through it. As usual, it's an organic form.