OregonJim wrote:
It looks like mold to me, but I could be wrong. The ribbons might have been stored in a damp basement or shop at some point. If it is mold, then you run the risk of spreading it into your typewriter.
Yeah, I tried to scrub it but it is persistent, the box of the ribbons show liquid trace, so it should be mold like you say. I bought these really cheap but I guess there is no way to salvage them?