Wow! I am in love with this thread - Madeira FS20 Blackcore.
It is 80% viscose and 30% metallis. Very soft after sewing but strong! According to Madeira, it has a textured polyester filament core with a metalized polyester foil wrap. Regardless of what or how it is made, I had NO trouble with it at all.
I used it on silk, cotton, and some woolen. I was able to use it for some nice fancy hemstitching, even using a wing needle size 120/19. There wasn't any fraying or breaking of thread on the sewing machine. I also did some free motion stippling and that turned out beautiful! For regular sewing, I used a needle size 100/16.
My embroidery machine loves it! Threads easily (again, because of no frayed ends), didn't break at the high speeds, and sewed out a gorgeous stitch that sparkles.
You can see how the red just pops out. The other threads used are Marathon (polyester filament), polysheen Mettler, Isacord. The Madiera red makes such a difference!
Serger up next and no problems on the cotton, or the silk. WhooHooo! Now I need TONS more colors!
I got my thread from Purple Moose Designs. Oodles and oodles of colors! Fabulous place!
I think my silk scarf needs some more embellishement with the Madeira red and maybe some fringe all around. Later!