I agree, the coin does appear to have some sort of residue left over from a past cleaning, but not being able to examine the coin firsthand makes it difficult (at least for me) to say with certainty.
What is listed on the insert of the coin's PCGS
holder? Straight grade or "Details"?
Just my opinion here, but I would not purchase this coin regardless of its grade. There are too many attractive Vancouver coins available in the market to accept one with visible surface issues / distractions such as those found on this coin.
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