u/Initial-Slice3109

I checked on the pack of 4g weights that came with my rival 600 and I saw this what could only be described as green slime on all the weights. The texture is slightly sticky, similar to a silver of jolly ranchers. For context I have had this mice and the weights for around two years. I have never used the weights in the mouse though on occasion I do fidget with the weights in my hand. The last time I did that was around a year ago. I have tried to remove this stuff but it seems to grow back everytime. I have used soap and alcohol. I really want to ask someone in the science or biology subreddits as based on how it grows back and the texture I do not think it is metal oxide