Thanks Deb for the fascinating tutorial "Fibre Fossils" found here. I gave it a try with some success. I was unable to get the Golden Heavy Gel Matte that you use but impatient as I am I purchased Atelier Impasto Gel instead.
I stitched a sampler nine patch with various materials and threads.
Then hemmed and glued it onto a small stretched canvas. Waited 24 hours for the glue to dry then gave it one coat of impasto gel. It did "fossilise" quite nicely although the maroon material went very dark. Again 24 hours later I gave it another coat of the gel to get a slightly harder effect. I probably wouldn't have needed to do this if I had purchased the Heavy Gel! Anyway it was a good experiment and I'm now working on some more small pieces.
It's fun to play!