What do you make of the look on the rims on this coin?

I was watching this coin at Heritage--a very nice uncommon coin in an uncommon grade. Out of my league and out of my collection goals, but it was worth keeping an eye on.
It sold for about half the low end of estimate IIRC, basically the opening bid, much to my surprise. Overall the prices for the Japan gold were a bit over the map compared to the estimates, but this one was extremely weak so I'm guessing I wasn't the only one questioning it's appearance (or it's more common than I realized or than the pop report would suggest--it is a top pop BTW).
So, other than a couple spots...the rims are what really put me off. Can anyone tell me what 'puttying' gold looks like when it 'turns' (I remember reading about that a long time ago on the US threads), and if this is it--or something else I should know the name of?
These are screenshots I took--on of the coin only shot, one of the slab shot and one of the full slab view (both cropped) and one where I zoomed in and circled what I was looking at. The look was pretty consistent between the coin view/slab view which made me really take not--not just a trick of lighting or anything. Or, maybe it is.
Comments
It does look odd.
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It does look like a residue.
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Looks like a penguin doing the Tango.
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There are definitely some copper spot remnants so perhaps a conservation gone bad? Just to sidetrack my own thread, does anyone have a good picture of a 'bad dip'...not the overdipped/washed out look, but the kind where the coin 'turns in the slab'? I see some yucky blotchy brown toning sometimes on otherwise high graded coins (both TPG) and I'm assuming that's what happened there too.
Any photos of the so-called putty?
I know almost nuttin about putty but I have seen pics of gold that was said to be puttied and had that pink color.
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