Interesting Surface alterations with laser, possible future of doctoring?

Aspie_Rocco

I was sent this video just now and thought it was interesting how a laser can clean a coin or alter the surface. Is this a new way unscrupulous folks can doctor coins or is there an obvious tell, aside from the face tattoo in the video? As I saw the color change I was oddly horrified. https://m.facebook.com/reddit/videos/1506151283140869/?extid=CL-UNK-UNK-UNK-IOS_GK0T-GK1C-GK2C&ref=sharing

dcarr

It will apparently burn off the oxides, but leaves a permanent matte finish.
I can do essentially the same thing via bead-blasting.

Zoins

@Aspie_Rocco said:

Wonder what this sells for?

Weiss

I seem to recall seeing this many, many years ago. Certainly something to consider, but I don't think it's anything new.

fathom

Not great pics but that appears to have an altered surfaces look.

jmlanzaf

@Weiss said:
I seem to recall seeing this many, many years ago. Certainly something to consider, but I don't think it's anything new.

Laser ablation

stawick

@Zoins said:

@Aspie_Rocco said:

Wonder what this sells for?

I'm holding out for the Post MaLincoln variation.

Namvet69

Is the burn off measurable?

PerryHall

The color and surface texture make this an obviously altered coin. Lasers have been used on coins for many years especially to remove hairline scratches from proof gold coins.

Aspie_Rocco

@PerryHall said:
The color and surface texture make this an obviously altered coin. Lasers have been used on coins for many years especially to remove hairline scratches from proof gold coins.

Is that a successful way to remove hairlines or does it permanently alter the appearance?

PerryHall

@Aspie_Rocco said:

@PerryHall said:
The color and surface texture make this an obviously altered coin. Lasers have been used on coins for many years especially to remove hairline scratches from proof gold coins.

Is that a successful way to remove hairlines or does it permanently alter the appearance?

The narrow laser beam melts the surface along the hairline thus closing the groove. There have been past threads here discussing the lasering of hairlines on proof gold coins. Those that have seen the results of this process say it can be detected once you know what to look for. I've never seen it myself so I'm just repeating what I've read in past threads.

LukeMarshall

I read a story on the forum of a classic gold coin in a straight graded holder that was apparently lasered - you could tell if you tilted the coin? I would think it leaves a checkerboard pattern or some other diagnostic

Broadstruck

Beyond proof gold lasers have also been used on Morgan $1's.

lilolme

@Weiss said:
I seem to recall seeing this many, many years ago. Certainly something to consider, but I don't think it's anything new.

Agree not new but I don't know how old. There are many videos on youtube and I will post a couple below.

@Namvet69 said:
Is the burn off measurable?

It appears the answer is yes. Here is a long research summary on some metals including copper, silver and thin gold. Toward the bottom 'Conclusions' gives a summary of each.
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https://www.sciencedirect.com/science/article/pii/S1296207421001643
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This video sort of briefly summarizes the above article but they are not related.
3 minutes
https://www.youtube.com/watch?v=0TcHNsPr9Nw
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Some coin video examples.
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50 seconds
https://www.youtube.com/watch?v=-oskWpQK4B0
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40 seconds
https://www.youtube.com/watch?v=qibqS6i3gc4
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30 seconds
https://www.youtube.com/watch?v=Xjt-_kHtWok

jmlanzaf

@LukeMarshall said:
I read a story on the forum of a classic gold coin in a straight graded holder that was apparently lasered - you could tell if you tilted the coin? I would think it leaves a checkerboard pattern or some other diagnostic

Checkerboard?

jmlanzaf

@PerryHall said:
The color and surface texture make this an obviously altered coin. Lasers have been used on coins for many years especially to remove hairline scratches from proof gold coins.

You can also use them for less nefarious reasons such as carbon spots.

lilolme

Previous (and old) thread about 'lasered' gold (mostly).

https://forums.collectors.com/discussion/709001/can-anyone-show-me-a-picture-of-a-coin-that-was-lasered

Edit: and one more

https://forums.collectors.com/discussion/1000007/lazered-coins

Namvet69

@lilolme that sciencedirect paper is a great read. So the molecular surface alteration, micro melting, discolorations can be seen under microscopic examination. This topic is very interesting. Peace Roy

ricko

@lilolme.... Thank you for the links and videos. Very informative. I have a laser that could do some of this... Will have to try it on a couple of old cents/nickels. Stay tuned - (could be a long tune, got lots of other things to do ). Cheers, RickO