Paper Opinion Please

This just came in today. I purchased a page of revenues on ebay recently, which included R77-80. I really bid because of this R80, despite it's awful centering and cut cancel. Thankfully I did not need to give much for the lot. I think others were scared off of bidding because of the low res scan. But I thought it was worth taking a chance as I recognized this late style cancel and was hoping for a silk, of which I do not have. The cancel is April 12, 1871.

See the high res scan below, it looks very silk like, with multiple threads, although no distinctly blue ones...

You'll see that a lot on R80s, even more so than other denominations. Paper that looks like it's the right color and texture, but no blue silk threads to be found. The only way it would be a silk paper is if it were part of a multiple where one of the stamps had blue silk threads. Once separated from the other stamps, since it cannot stand on its own merits, it cannot be considered a silk paper.

Generally speaking, the experimental silk paper is bright white. This is not one.

I've seen a mention of "straw" paper before, although I can not remember if it was in reference to revenues. I've seen this type of paper with golden "straw" fibers, similar to what you see above. Is this a thing?