I’ll never forget the day I saw these threads at my local shop. This was a needlepoint only shop, owned by a woman with very strong opinions about needlepoint.
I have no idea why she was carrying a thread that was designed to give the look of time-worn samplers, so slight variation in color and shading but not too much.
I bought a skein, tried it and loved it.
I still do.
Now you can learn about this thread in a post from the cross stitch blog, Star Stitch.