cleaning and die polishing

WWBillman

How do you tell the differeance between cleaning and die polishing?

I have a PCGS graded SLQ coin and along the edge of lady liberty's right arm and shoulder there is what looks like a bunch of little scratches it is as same on the other side around the edge of the shield but not as bad. Without magnification it looks like frost. I am using 16X magnification. It looks like the scratches may be raised which is why I am thinking die polishing.

Any opinions?

gmarguli

Cleaning lines frequently go in one direction. The luster is not there after the cleaning or at least it is impaired. Cleaning lines are also dug into the coin.

Die polishing lines go in all directions. There is original luster there after the polishing. The lines are also raised above the original surface of the coin.

stman

I think you are correct in your assumption that if the lines are raised it is probably die polish lines.

Dog97

If the lines do not run all the way up to the design elements it's a cleaning as die polish runs all the way up to the design.

Lakesammman

Agree with most of the above - I've been surprised how many die polish lines are found on the devices, even the deeper portions of the die....don't know why but they do....perhaps the first effort to remove rust was a wire brush, then finer (more planar methods that couldn't extend into the depths) methods confined to the field. Bottom line is, die polish lines result in raised lines on the coin.

nwcs

Now whizzing and polishing can leave different looks on a coin. Polishing can leave hairlines in all directions. Whizzing generally is in one direction. But you can always tell, as others said, by whether the lines are raised (die polish) or recessed (some form of cleaning). You can also tell if it is concentrated heavily in one area. I have a nice morgan that is untouched except around the motto on the reverse where someone heavily polished it before I got suckered with it. Don't know why they only polished there, but it got bagged by PCGS because I couldn't see it when I sent it in. Learned more and saw it more clearly when they got back. ARGH!

clackamas

The only sure fire way to tell with many lines is to see if they are raised or not. One thing I look for is if the line seems to go right through something like the date or any other raised part. If it does its die polish. However die polish can creep into the devices and can be apparent on smooth surfaces like a face. Most of the time its not hard to tell but sometimes you have to look hard. The 1935 Lincolns are notorious for heavy die polish. You have to look close at these to see if it was actually cleaned.

dorkkarl

this is where the halogen lamp i described in another thread comes in handy. shine the light across the coins surface from the right side, practically parallel to the coin's surf. if the lines show bright on the right, dark on the left, they are raised, & are die polish. if the lines are dark on the right & brilliant on the left, they are etched into the coin's surface, from cleaning.

i have found this technique to always be reliable. NOTE that it may not work through a slab's plastic though! i imagine the plastic will distort the light distribution.

hope this helps. this type of light (& good magnification) is the best investment you can make for fighting back at doctored coins.

K S

Gilbert

Well, I can't confirm or deny DorkKarls technique, but I can add that with the halogen light hairlines tend to reflect color schemes, whereas die polishing lines should give as uniform appearance as the other unmarred surfaces.

The raised lines versus incuse lines is the best test, and you should be able to see it with 16x

And there are instances where die polishing can be uni-directional (die applied to a stationary wheel brush) and whizzing can be in a circular or otherwise multi-directional pattern (rotary or oscillating tool).