I cheated. Years ago, there was a sale on nice little potholders with insulbrite silver on each side of the outside and some inexpensive binding. I think they were going for about fifty cents a piece. I bought a 12 inch stack of them and just covered 2 in my favorite quilting fabric and binding. Those two have lasted over 20 years (I can't kill them!) and they've never failed me with regards to protection from heat. I suppose the remainder will be found in my stash after I pass on. I should leave instructions for the finder to do what I did and then have her will the rest to whomever finds her stash!