I went to a one-hour lecture on quilting with silk fabric at Puyallup a few years ago.

You don't need to interface the silk, but you do need to wash it in hot water before you cut it. This shrinks it and makes the weave denser, so fraying is less of a problem.

Even then, it's still a good idea to cut it with a pinking blade.

Anne in Vancouver, Canada

Definitely use pinking shears (or pinking blade in your rotary cutter) to cut down on the raveling. I used a beautiful silk to make some embroidered placemats, and didn't figure out the pinking until the very last one!

Maggie in E. Central Illinois

My Friend pieced a silk duvet cover and not only did she find it very slippery to work with, it UNRAVELS (frays) to the point that it comes apart.
So, yes, I would use a light weight stabilizer and/or a serger (or a similar type stitch on your sewing machine).
I have also been told to use pinking shears to help minimize the unravelling.

Jean in a soon to be snowy Windsor, ON

I have a lot of silk; some from cast-off clothing and some from my daughter's trips to Nepal and India. It is the light gauzy silk. Should I interface the pieces before piecing together? What about wall hangings vs bed quilts of silk? Is it strong enough to withstand wear on a bed? Do I need to piece with silk thread? Thanks in advance.

Diana in Canada