Jboyd
I can't tell you for sure what kind of silk it is. I bought several yards off of the big auction sight a few years ago and that is what I use. It is real thin but real strong. A great backing. I use titebond lll and just put a nice even layer of glue on and lay the silk down. You got to watch it though or it will wrinkle up on you when the glue starts to dry. I just keep it tight where the wrinkles are showing until it is fairly dry. Here is a pic of the silk I use.