Strange pigmented things in Subway napkin

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The discussion centers on observations made using a USB microscope to examine a Subway napkin, revealing colorful dots in various shades such as yellow, light blue, green, red, and pink. The napkin is labeled as containing "100% recycled fiber," prompting inquiries about the source of these colors. Participants suggest that the colored dots are likely remnants of recycled paper that have not been affected by bleaching processes, which typically whiten the paper. It is proposed that the presence of these colors indicates a significant amount of colored paper, possibly from recycled magazines, which retains colorfast glossy fragments during recycling. This highlights the complexities of recycled materials and their visual characteristics.
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So I was playing with a USB microscope at my desk, and I just viewed a Subway napkin with it. Attached is the picture I saw at ~75x magnification

There's dots of all sorts of colors.. yellow, light blue, green, red.. even pink.
Does anyone know what the colored dots might be?

There's a description on the napkin saying "contains 100% recycled fiber."
 

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could be recycled polymer fibers.
 
I can see this type of thing barely in my rough notebook, made out of unbleached recycled paper.

These coloured bits and pieces are just remnants of recycled paper unaffected by the bleaching agents, which turns them white.
 
If they're recycled paper, why are there so many colored spots? Is there really that much colored paper being recycled?
 
They are probably recycled magazines, with colourfast glossy picture fragments that would certainly survive bleaching if any, and remain attached to the fibres in the recycling process.
 
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