When you look up the definition of quilt, it says three pices kept together with stitches. It does not say that it must be cotton. The most expensive quilt ever sold (For $70,000!)had silk, wool, polester, cotton, you name it. Anyone who would laugh at your use of a different fabric, is not someone I want to know. How rude! Your art piece is well done, unusual, and very artistic. What else is there to say?