Silver is going to be tough. If it were gold or bronze, mica powder would work well. There are some “sparkly” glass paints — Unique Class Colors and Colors for Earth both offer them. There are some dichros that are silver, but that would be very costly and cutting a continuous rimmed border without breaks would be darned near impossible.
Where it is a display piece rather than functional (or so I assume, since it is going into a stand), I think a good solution would be to apply the “silver foil” that you find at places like hobby lobby to the piece AFTER it is finished (this is not silver, but aluminum).
Apply white glue to the place where you want the foil to stick. Tear the foil into small pieces and apply to the back. Carefully burnish the foil down with a soft cloth. Then use a sealer of some sort to protect the foil. Spray paint or the Krylon clear sealers work OK — if you really want to get serious, use a resin. BTW, I suggest small pieces of the foil, because large pieces will be hard to apply smoothly and you’ll see the seams. With the small pieces, well, you’re accepting the seams and uneven texture in all its glory and calling it intentional .
Another option would be to leave the rim clear, and then use a chrome spray paint after firing.
Fused Glass Designs
dba Jester’s Baubles