Pristine Vintage black silk frock,pockets and elastic waist.

Simple and elegant. Pockets. 3/4 pleated sleeve. Dress up with a silk scarf and heels or down with a denim jacket and flats. Vintage. No lable. By my research, I'd say it is a true large. Flawless condition. I bought it years ago but I'm too lo g waisted for it to look right on me. The fabric feels so good to the touch. Silk?