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Author Topic: Dangerous Laser Tooling Example  (Read 3005 times)

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Offline carthago

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Dangerous Laser Tooling Example
« on: January 20, 2013, 08:33:03 pm »
Modified 2-26-13 to update photo location.



A few months ago, I posted a request for opinions on a Denarius of Marc Antony that I owned.  The topic regarded another coin that I found in a prior auction that looked just like mine, except in a much more worn state.  The topic can be found here:

https://www.forumancientcoins.com/board/index.php?topic=84483.0

Fast forward several weeks.  I've since taken my coin to 2 major ancient coins shows and discussed it with several highly qualified dealers.  Suffice to say I'm pretty sure it is tooled and I'll explain why, as it was explained to me.  First off, though, credit should be given to Barry Murphy who said it was tooled in the original post above, but didn't really explain how so I'll do it as I understand it.

In short, there was apparently a Bulgarian (what's with those enterprising Bulgarian's?) a few years back that was purchasing worn, reasonably high value coins and tooling them with a laser.  They are very dangerous and the way to tell is to find the prior coin (like I did) and/or find a die match and look for the differences.   Under magnification, I'll admit I don't have a ton of experiencing looking at these but there is no metal movement that you would expect with typical tooling.  To me, it looks quite normal.  Again, I'm not the expert and hopefully don't have any others in my collection to compare.

I'm putting up 4 photos: tooled, original, what I believe is a die match, and about a 50-60x magnification view of the tooled coin in area that was tooled.  If you compare the tooled coin to the die match, it is clearly off in hair details.  It almost doesn't seem like a die match, however, if you compare the original to the die match, they are right on and if you compare the original to the tooled it is right on.  

Anyway, I share this with the community to know this stuff exists.  It's very dangerous.

The tooled coin:



The original coin:



Magnified view of tooled area



The candidate die match





Offline carthago

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Re: Dangerous Laser Tooling Example
« Reply #1 on: January 20, 2013, 08:42:58 pm »
Here is perhaps a better way to compare the 3 different coin photos:


Offline marcos x

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Re: Dangerous Laser Tooling Example
« Reply #2 on: January 20, 2013, 09:07:33 pm »

In short, there was apparently a Bulgarian (what's with those enterprising Bulgarian's?)

Bulgaria is rather poor that is probably a good motivator.  :tongue:
when I die make sure to put two coins on my eyes for the boatman......make sure they are not fouree's

Offline Britanikus

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Re: Dangerous Laser Tooling Example
« Reply #3 on: January 21, 2013, 02:14:55 am »
It is against the law for you to own ancient artifacts, coins ................. in Bulgaria .
There is a lots of replicas sold all around clubs museums ...... and also some of them are ending on ebay and other websites .
The reason so many are made there 1st the law and yes the economic situation is not great
I'm going on vacation in Bulgaria this month and I have friend  who makes replicas "I know him from childhood and he is  making  me some dies with my and my wife faces. So soon i will mint my own denarius with my name  :D

Offline carthago

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Re: Dangerous Laser Tooling Example
« Reply #4 on: January 21, 2013, 09:10:13 am »
So soon i will mint my own denarius with my name  :D

Make sure you pay off the Praetorians.  Their support will be key to you success!

petier

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Re: Dangerous Laser Tooling Example
« Reply #5 on: January 21, 2013, 10:37:31 am »
<<<<<<<<<<<<It is against the law for you to own ancient artifacts, coins ................. in Bulgaria .>>>>>>>>>

Britanikus better check your facts before putting false info here.


Offline Britanikus

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Re: Dangerous Laser Tooling Example
« Reply #6 on: January 21, 2013, 02:56:24 pm »
<<<<<<<<<<<<It is against the law for you to own ancient artifacts, coins ................. in Bulgaria .>>>>>>>>>

Britanikus better check your facts before putting false info here.


Yes metal detecting is against the law in Bulgaria
"The ink was barely dry on Bulgaria’s new antiquities law requiring all current holders of archaeological finds including coins to register the finds, before the new law was challenged. Bulgaria is one of several European countries that has become increasingly sensitive to archaeological finds of “cultural patrimony” being exported without approval of the government.
http://www.novinite.com/view_news.php?id=119024

http://www.novinite.com/view_news.php?id=95219

SO HAVING ANTIQUES IN YOUR HOME IS AGAINST THE LAW AND YOU ARE CRIMINAL
 
http://www.economynews.bg/%D0%BF%D0%B0%D0%B7%D0%B0%D1%80%D1%8A%D1%82-%D0%BD%D0%B0-%D0%B0%D0%BD%D1%82%D0%B8%D0%BA%D0%B8-%D0%B2-%D0%B1%D1%8A%D0%BB%D0%B3%D0%B0%D1%80%D0%B8%D1%8F-news2778.html


SO Don't TEL ME TO CHECK MY FACTS CHECK YOURS so if you are to collect ancient coins you have to ask for permission from the government of Bulgaria and the coins you collect must come outside Bulgaria with proper documentation .Bulgaria is poor and this is the reason for many forgeries to come from there " CHECK YOUR FACTS"

Offline Britanikus

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Re: Dangerous Laser Tooling Example
« Reply #7 on: January 21, 2013, 03:15:50 pm »
http://www.novinite.com/view_news.php?id=79490  If we live in Bulgaria all of us  will be considered criminals ;)

Offline Britanikus

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Re: Dangerous Laser Tooling Example
« Reply #8 on: January 21, 2013, 04:23:26 pm »
I will pay in Denarius  ;D I have to find a good way to make blanks not an easy task if you live in apartment with no garage .Maybe i will buy my way up in the forvm :) ;D

Next time we vote for member of the year ;D

Offline Joe Sermarini

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Re: Dangerous Laser Tooling Example
« Reply #9 on: January 21, 2013, 04:40:21 pm »
There can't be any doubt that the coin is made from the more worn but identical example.  I am not entirely convinced it is laser tooling because I have never heard of a laser that could do that.  I don't have a better explanation.  Without the laser story, I would have thought it is a cast made with reengraved molds.  If anyone can provide more information on the type of laser that could do this, please let us know.
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Offline Andrew McCabe

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Re: Dangerous Laser Tooling Example
« Reply #10 on: January 21, 2013, 04:51:35 pm »
This is very interesting. Comparing the "candidate die match" with the "tooled coin" shows indeed that the hair above the ear is in a different pattern, and therefore must have been tooled, but that otherwise it's the same die. So the "tooled coin" does appear to have been re-engraved from the worn coin.

I myself argued against the possibility of tooling when the coin was originally discussed as I thought the relative vertical layers of the surface wouldn't allow it - more simply, it seemed to me that there wasn't enough relief to play with. But it seems that the tooler has perhaps cut back on the entire coin's surface and somehow created the vertical space to make this happen.

So, how can we all learn to recognise it? I think the tooled Antony does have a certain implausibility as a struck coin, a look-feel that makes one hesitate. Can we put words to it?

One typical way to recognise tooling in hair is that the thickness of hair in an un-tooled coin is determimed by the size of the ancient tool but the distance between hairlines might be very narrow; the reverse applies on a tooled coin: the distance between hairlines is determined by the smallest size of a modern tool, and in carthago's enlargement we see relatively speaking broad valleys where the coin was tooled, but sharp points/lines on the hair itself. It should be the other way round.

Perhaps luckily for me, very few of my coins are anywhere near the sort of apparent quality that this craftsman was producing.

mariela s

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Re: Dangerous Laser Tooling Example
« Reply #11 on: January 21, 2013, 04:53:34 pm »
I personally do not think that the coin is tampered with, was a laser or otherwise. For me it is 100% authentic.

Offline Lee S

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Re: Dangerous Laser Tooling Example
« Reply #12 on: January 21, 2013, 05:39:35 pm »
I personally do not think that the coin is tampered with, was a laser or otherwise. For me it is 100% authentic.

With all due respect Mariela, In that case, how do you explain the fact that the first 2 coins at least, are perfect die matches, except for the hair?

  I am very interested in hearing you defend your statement, and explaining how you arrived at that conclusion....

Offline Lee S

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Re: Dangerous Laser Tooling Example
« Reply #13 on: January 21, 2013, 05:48:54 pm »
This may be of some use....

Offline mix_val

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Re: Dangerous Laser Tooling Example
« Reply #14 on: January 21, 2013, 06:26:30 pm »
how do you explain the fact that the first 2 coins at least, are perfect die matches, except for the hair?

Sorry to be picky Lee but there are many genuine coins that are die matches.  What gives these two coins away is that the flans are identical, something very difficult to achieve hand made and secondly, the two coins have many of the same imperfections (ie wear marks like scuffs and dings).  It's beyond belief that these coins could have suffered the same wear in decades of use unless they are modern and cast from the same parent coin or the pictures are of a coin before and after tooling.  
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Offline carthago

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Re: Dangerous Laser Tooling Example
« Reply #15 on: January 21, 2013, 06:59:16 pm »
I personally do not think that the coin is tampered with, was a laser or otherwise. For me it is 100% authentic.

Don't feel bad, I did too when I bought it.  Others dealers that I showed it to as well thought it was fine...until I showed them the picture of the worn coin.  I'm disappointed because I liked the coin.  It's since been returned.

There can't be any doubt that the coins is made from the more worn but identical example.  I am not entirely convinced it is laser tooling because I have never heard of a laser that could do that.  I don't have a better explanation.  Without the laser story, I would have thought it is a cast made with reengraved molds.  If anyone can provide more information on the type of laser that could do this, please let us know.

Yeah, it seems Start Trek but I was told this by 2 dealers you would recognize.   Barry Murphy...if he's around here anywhere...was mentioned as a somewhat expert on the issue.  Barry mentioned in my original post that he thought it was tooled and I thought he was nuts because I couldn't see any evidence of it. 

Offline carthago

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Re: Dangerous Laser Tooling Example
« Reply #16 on: January 21, 2013, 07:00:37 pm »
This may be of some use....

Please share how you did this.  I'm Alt-Tabbing between windows and it's a bit analog compared to you elegant solution. 

Lloyd Taylor

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Re: Dangerous Laser Tooling Example
« Reply #17 on: January 21, 2013, 07:25:53 pm »
Interesting.  Sure beats Propecia!  :evil:  

In my opinion the coin is most probably the result of a very high grade lost wax cast with the hair "tooled" into the single use wax master using a very hot fine probe, prior to casting.  

I doubt that the poor Bulgarian forger has access to a high energy, pulsed laser capable of metal ablation (http://en.wikipedia.org/wiki/Laser_ablation ). Its not the sort of kit that is readily available, nor is low cost, nor is it something that can be weilded effectively by the unskilled/untrained.  Much easier to fuse and remove wax from a lost wax master - this would be consistent with the "fused" character of the hair detail under magnification.  Sure it requires considerable skill to do properly , but done properly the results are very hard to detect and for high-end scarce coins the price achieved warrants the additional effort required.

Offline Lee S

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Re: Dangerous Laser Tooling Example
« Reply #18 on: January 22, 2013, 12:16:09 am »
 
how do you explain the fact that the first 2 coins at least, are perfect die matches, except for the hair?

Sorry to be picky Lee but there are many genuine coins that are die matches.  What gives these two coins away is that the flans are identical, something very difficult to achieve hand made and secondly, the two coins have many of the same imperfections (ie wear marks like scuffs and dings).  It's beyond belief that these coins could have suffered the same wear in decades of use unless they are modern and cast from the same parent coin or the pictures are of a coin before and after tooling.  

   Sorry, perhaps I did not make myself clear.. But that is Exactly what I meant to say... Even with an inexperienced eye I can see it is physically impossible for BOTH coins to be untampered with and original!

Quote from: carthago on January 21, 2013, 07:00:37 pm
This may be of some use....

Please share how you did this.  I'm Alt-Tabbing between windows and it's a bit analog compared to you elegant solution.  

  I just dragged the 2 images out to the same proportions then cropped them down to the same image size ( using 2 open "paint"s and alt tab actually!, I find it the easiest app for simple tasks) , then used the website http://picasion.com/ to merge them into a gif file...  ;D

Offline Andrew McCabe

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Re: Dangerous Laser Tooling Example
« Reply #19 on: January 22, 2013, 12:39:12 am »
This is tough to understand so I urge patience on those surprised by this. I was too, and I argued back in the thread a couple of months back, but I've had some time to think over and digest it, and to consider the evidence again. I was wrong then, and carthago - and Barry Murphy who noticed details I overlooked - are right.

Whatever we call the process, carthago's coin has been altered from the worn example, and its flan is identical in shape. It is a die-match to the coin with the flan crack, but in the course of being altered, details at the highest points were made-up that do not match the die details of the coin with the flan-crack, and the nature of the alteration process has produced hairlines that are not natural because rather than hairs being engraved in a die face, it is the grooves between the hairs have been engraved in a worn coin. The ear's shape is also changed compared with the die-match as a result of being cut back, and the height of the forehead has been noticeably decreased by cutting out the eye socket above the eye, to enhance details around the eye. etc.

I think the evidence of the coin having been cut-back in various places rules out it being formed by any means except direct tampering on the worn coin's face. You cannot produce this effect by altering a mould - if you cut into a mould it has the opposite effect to cutting back a coin - it adds metal rather than removes it.

So there are only two coins illustrated in carthago's first post. Not three, two.

The good thing is that such a technique should be recognisable. It's a very sophisticated form of tooling, but as with all tooling, the requirement to engrave positively rather than negatively, and the requirement to cut back fields in order to create apparent relief, create recognisable effects. The symptoms I've described are symptoms of tooling.

Lloyd Taylor

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Re: Dangerous Laser Tooling Example
« Reply #20 on: January 22, 2013, 01:18:27 am »


I think the evidence of the coin having been cut-back in various places rules out it being formed by any means except direct tampering on the worn coin's face. You cannot produce this effect by altering a mould - if you cut into a mould it has the opposite effect to cutting back a coin - it adds metal rather than removes it.

....... It's a very sophisticated form of tooling, but as with all tooling, the requirement to engrave positively rather than negatively, and the requirement to cut back fields in order to create apparent relief, create recognisable effects. The symptoms I've described are symptoms of tooling.

I think you fail to understand the lost wax casting technique which involves three stages to create a mold from which the coin is cast:
1) The impression of the coin (an original mold if you like) - i.e. a negative of the coin. This master mold is in flexible silicone material unsuitable for casting but capable of producing as many wax master casts as the forger may care to produce.
2) The creation  of a wax cast from the impression i.e. a positive of the coin in wax (not metal). This wax cast can be adapted/tooled if the forger so desires or used as is.
3) The creation of a single use mold from investment clay that entirely surrounds the wax coin, but for fine entry and exit pouring points. This investment clay mold is thus cored by the wax cast of the coin and once fired is capable of retaining molten metal. The wax is removed on firing to create the final mold in a single piece (i.e a negatve of the coin) into which the metal is cast. On cooling the investment mold is broken to release the cast metal coin.

Note the modification of a lost wax master is exactly as you describe except it occurs on the wax positive rather than a metal coin - the effect is exactly the same in all characteristics as tooling.  The wax master is cast from the original silicone impression of the worn coin, only cast in wax rather than metal. The "tooling" work is then done on the wax cast which becomes the core of the mold from which the coin is cast. On firing of this mold the wax melts away leaving the hollow void into which the metal is then cast.

It seems few understand the difference between crude direct casting using a two piece mold lifted directly from a coin and the tree stage lost wax casting technique. The latter is the preferred route to high grade casts because it is a much more controlled process enabling the fabrication of individually tailored fakes through subtle adaptation of each wax master which is only used for a single cast (single use because the hand crafted wax master is destroyed in the firing of the investment mold prior to metal casting into the void it leaves behind).


Offline Andrew McCabe

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Re: Dangerous Laser Tooling Example
« Reply #21 on: January 22, 2013, 01:32:43 am »

I think you fail to understand the lost wax casting technique which involves three stages to create a mold from which the coin is cast:


OK I stand corrected on this. I'd forgotten (despite visiting the Royal Academy's superb "Bronzes" exhibition) about how lost waxes are made.

So we agree that the coin was made by cutting back/into something. Either a wax pattern or a worn coin. We agree it is a forgery or remake, and thus the coin is condemned. Now it comes down to which would be easier to do. I've no vested interest in arguing any case, as even in the "tooling" case I don't know what techniques would have been used. The difference only becomes significant if the forger starts to churn out more examples through the lost wax process, each slightly different as each would required individual engraving of the one-time wax model.

We can only conclude what happens if either another forgery appears that also looks as if it was made from the same worn coin, or if the original worn item surfaces. Otherwise I will continue to believe that tooling the original coin was probably easier than going via a wax model.

Lloyd Taylor

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Re: Dangerous Laser Tooling Example
« Reply #22 on: January 22, 2013, 01:39:01 am »
We can only conclude what happens if either another forgery appears that also looks as if it was made from the same worn coin, or if the original worn item surfaces. Otherwise I will continue to believe that tooling the original coin was probably easier than going via a wax model.

Agree... I think its a case of watch this space!  If I was the forger, the fact that I could retain or sell the original coin, plus the money in the pocket from a "different"  tooled fake, would be an attractive economic proposition - my margin (or return on effort involved) goes through the roof compared to the alternative of direct tooling and resale of the tooled original.

mariela s

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Re: Dangerous Laser Tooling Example
« Reply #23 on: January 22, 2013, 02:11:51 am »
This may be of some use....

Much easier to buy a real coin, which is then copied and cast, and worn to the extent that it presented, worn in antiquity coin than to buy real worn coin, and then come to carve achieve high quality.
In the second case, an error in the hand and work your going to hell.

For me personally, I think the one in this case is real quality piece and the other is a copy, fake.

Offline carthago

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Re: Dangerous Laser Tooling Example
« Reply #24 on: January 22, 2013, 08:41:24 am »
One thing that I failed to mention is that both of the coins had apparently identical weight according to the auction descriptions.  I didn't weight mine, but the auction it came out of said it was 3.68g and the suspected original was 3.69g.  Mine was sold in 2009 and the original (if it is indeed the same coin) was sold at auction in 2005. 

If tooled by laser, magic, or the Dark Side Force in a way that it removed material, I wonder if the weight would change appreciably?  Alternatively, having it virtually the same weight in my mind adds further evidence supporting that it is the same coin.  Wouldn't it be very difficult to replicate the weight in a cast?

Btw, Lloyd, thank you very much for your education explanation on lost wax casting!  Very much appreciated.  I did not know how it is done. 

 

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