More like a polishing line I'd think Flow lines would radiate from the center, because that is where the die forces the metal.
Flow lines emanate out in a circular sense, much like dropping a stone in a body of water, and watching the waves move outward. The lines on the reverse of your coin lead me to believe that it's been cleaned, and not 'hairlined' as most hairlined coins I've seen are random and not uniform.......
Do you have the coin in hand? Those photos are deceiving. I think they are planchet striations. Look at the obverse in this photo. https://coins.ha.com/itm/patterns/1...9-4889.s?ic4=ListView-ShortDescription-071515
Now that you say that.. Too parallel and straight for what I said. Thats a hard coin to photograph, I can just tell.
If those are polishing lines then why does this and other Pollock 355 coins not show them? https://www.pcgs.com/auctionprices/item/1862-10-j-297-bn/60447/4946778202618935289 https://auctions.stacksbowers.com/l...-rarity-6-copper-reeded-edge-proof-65-bn-pcgs https://coins.ha.com/itm/patterns/1...4-4938.s?ic4=ListView-ShortDescription-071515
Are they raised? Or maybe this is like, a felt cabinet's friction made little micro abrasions? I'm not an expert. But thought it may be a possibility. Looking again I don't think so. Must just be a planchet thing if the other coins from the same die dont exhibit similar traits.
Neither one. The obv has some hairlines on it but what we see on the rev are die polish lines. You had it right the first time, straight and parallel is exactly how die polish lines are supposed to look ! That is one of the critical identifying characteristics of die polish lines.
It is a pattern Judd 387. It is a $10 gold piece means it on copper. There are a lot of patterns that are off metal printed on one metal yet intended for a different one. This is one of those coins. I have no idea why they did this maybe someone else can step in and answer this question