Hairlines on proof coins?

Weg

I just copied this from a recent thread:

Also, keep in mind, that Proof coins don't usually have hits and strike is rarely an issue. Far more times than not, it is the extent of hairlines which accounts for the grade on a Proof coin. And those hairlines don't show up well in images.

Are the above mentioned hairlines made from something such as a finger rub, or possibly from an attempt to get a coin into a SAFLIP and the edge of the flip created the hairline? Or are they somehow made at the mint? I can see where grading proof coins can be much more difficult than MS.

lkeigwin

Mint-made from polishing dies.
Lance.

edited to say
I was a little quick on the reply. Yes, hairlines that affect grading are post-mint damage often caused by rub or sliding. Many hairlines on proofs, hairlines in fields that do not cross devices, are from die polishing.

messydesk

<< <i>Mint-made from polishing dies.
Lance. >>


Nope.

There is a big difference between die polishing lines and grade-killing hairlines. Die polishing lines are raised in the coin, somewhat rough in texture, and do not adversely affect the grade. Hairlines are usually very fine lines caused by contact between the coin and some material capable of scratching it. These lines are not raised, and are usually very smooth and very straight. You may notice them diffracting the light when you view the coin, and they're often only visible when the light is just right, which is why they don't often show up in images.

tahoe98

...ditto.

Weg

Ahh, that makes sense. I just received the proof Lincolns and silver state quarters that were toning in grades from 64 to 69. I'll get them out and look for hairlines.

Edit: a couple more replys before I posted that made sense. Now my curiosity is higher yet; I've got to get them out for a closer inspection.

ModernDollarNut

Messydesk, right on. Would add that "rotating" ("wobbling") a proof under a light source is the best way to bring out hair lines as they will pop into view when the light is shining down perpendicular to the hairlines so their reflective incuse edges then reflect the light and they become visible.

Since one can not know in advance in which the direction possible hairlines are oriented, wobbling is necessary to scan a proof's surfaces.

coinguy1

My comment which you quoted from that other thread was with respect to man-made hairlines, not mint-made die polish lines or striations.

Weg

Mark, I'm glad you made it because it got me thinking and thanks to the replies,,learning.

Another edit: I'm seriously considering sending in all my First Spouse coins (after I get this last one taken care of). I want to keep all the OGP which includes capsules. To be honest, I'm scared to remove them from the capsules and put them in SAFLIPs and ship them in SAFLIPs. Understanding hairlines are created in and out of the mint, there are some (mint made) I have no control over. The ones you refered to I do have control over, which scares the H out of me.

COALPORTER

"Cabinet friction"

Wolf359

Proofs were individually made and when ejected from the press, were caught by a mint worker holding a cloth. The worker then used the cloth to polish the coin, leaving hairlines. One or two hairlines will put the coin into a PR67 holder, 3-4 into a PR66, etc. They are on the devices, not the fields usually and hard to see.

RWB

Minor correction - 19th/early 20th century proof coins were made on a medal press. These did not have ejection mechanisms. The coins were removed from the die by hand. Modern proofs are not touched by humans at all.

19Lyds

<< <i>Proofs were individually made and when ejected from the press, were caught by a mint worker holding a cloth. The worker then used the cloth to polish the coin, leaving hairlines. One or two hairlines will put the coin into a PR67 holder, 3-4 into a PR66, etc. They are on the devices, not the fields usually and hard to see. >>

Take a common proof, Loupe it, then polish it with a soft cloth, loupe it again and make note of how easily these coins hairline.

It's almost as if they have a clear thin film on them they scratch so easily.

I correct myself as I just did what I suggested and the proof sisn't hailine as much as I expected. It was a 1970-S Washington.

ColonelJessup

Take some common current proofs, maybe some silver coins from early 60's sets. Abuse them. At first very gently abuse them. In pockets, rubbed with tissue paper. You'll figure it out. Wait. YOU ARE DESTROYING NUMISMATIC TREASURES. Now find something even a little harsher with which to abuse them. Can't make an omelet without breaking some eggs.

When I was a kid we dropped pennies in CocaCola and rubbed mercury on Rosies. That was long after they took the coke out of Coke and soon after they took Mercury off the dime.

Weg

When the coins were removed by hand didn't they wear cotton gloves? I'm guessing that even if they were wearing them they could easily create hairlines, particularly on gold coins because of golds softness. Even silver, when I look at a proof Eagle if there was a speck of dust on it I don't know how anyone would remove it.

It appears that it is easy to damage proof fields. The only proof coins I've sent in for grading so far were sent in the gov lens which I did not want back. I'm considering sending all my First Spouse in, MS and Proof. Could SAFLIPs help create hairlines?