Die striations on proofs

Blade

I bought a 1942 PR67 merc dime yesterday. The coin has great mirrors and virtually no hairlines as you would expect for this grade. But it is loaded with die striations, which I haven't seen on modern proofs. Is that because this is a late die state proof? Or is it just the method of manufacture? Do most of the proofs from this era (1936-1942) have similar, obvious flow lines? You can see them with the naked eye.

coppercoins

Flow lines or die striations? They are different things. Die striations would most likely be caused by sanding or buffing the die, which has always been very uncommon for proofs. Die flow lines start developing on dies the moment they are put into place. I have seen a number of 1950s and 1960s proof Lincolns with die flow lines, not sure if that helps your predicament any.

While it might disclude a coin from a CAM or DCAM designation because of the lack of mirror in the fields it shouldn't affect the grade since this is a normal part of die wear.

Blade

CD,
Thanks for your comments. I buy mint state coins almost exclusively, so this is new territory for me. Based on your comments, I think these are flow lines.

They are very small lines in the mirrors, all radiating out from the central devices. They aren't scratches but part of the mirrors. O can't magnify them enough to tell if they are raised, but they look like what I have seen on other proofs of the era.

Since so few 1936-1942 coins are cam/dcam, I don't think that is an issue.