Matt's Counterfiet Gold Coin Thread

Matt, I commend you for your generosity and interest in educating others. There are many coin dealers who could do what you're are doing, but you had the idea and carried it through. Thanks!

Cast coins should have signs of a sprue being removed somewhere on the rim or edge; did you have the opportunity to examine the fakes for this? I suppose clever polishing could be used to make it difficult to find.

 

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It's getting late today and I'm working on a pretty good migraine but tomorrow I'm going to get the $2.5's out and really dig into the rims and see if I cant find where it was. If I find it I'll try to get a shot of it.

 

That's true. Fascinating thread. Get some rest and kick that migraine, Matt. Hope it wasn't due to eyestrain!

 

Very true! I remember this from the book numismatic forgery on casting coins!

I think the spure is there so you have something to 'grab' after the coin has been made, its very hot. I'll have to check the book again to make sure, I'm going through my second read on it, but its much harder to memorize everything in it! Doug said in another thread that you gotta study the book down to where you can remember everything, that's what I'm trying to do.

After the sprue is removed there is a seam where it was attached, so the forger may burnish the metal, or using other means (burnishing is just polishing the metal with other metal), or tool it so the seam is not visible.

 

This brings up a good point then. If they ARE depressions, which is caused from contact marks on the geniune host coin, then this coin must have been struck right? Because it retains the repeating depression from the geniune contact mark on the host coin.

I've never seen a depression on a cast coin. But who knows!

Doug, thanks for clearing that up too. Learn something new every day!

 

Something else I wanted to add, i just read over the sprue part on Numismatic Forgery. The author mentions that usually ancient coins are primary choice for casting, because of their irregular, gobular edge. The sprue is cut off and the point of attachment is burnished or filed (tooled). Or the counterfeiter may pack the entire coin, except for the spot to be repaired, in a wad of special insulating putty, and then use a needle torch to actually melt a small puddle right on the coin's edge. It blends in, but also is alot less noticiable on ancient coins due to their irregular edge.

Something else you might want to do, is from a cast is differential shrinkage. When the coin is expanded from heat, it contracts when it is cooled down. This results in a slightly smaller diameter, as well as the coin being thinner in the diameter. The weight will also be slightly less than the master, so weigh it too.

On the other hand, if it is struck, it should be in within (in most cases) the correct diameter, fineness, weight, etc.

 

As previously mentioned, the 'lost wax' process works best with small, thick coins, such as ancients, because of differential shrinkage of the materials used. The flatter,thinner, and wider the object being copied (think $10 Indians and Saints), the more the dimensions will be 'off,' and the more problems will be seen in the details. The best candidates for high quality copies using this method, in the US gold series, would appear to be the $2.50 and $5 Indians, I believe. (small/thick). Silicone rubber molds can be made of these and used to generate investment wax copies of the coins over, and over, and over. It's all outlined in Charles Larson's book, Numismatic Forgery, which is readily available, and cited earlier in the thread.

 

What do you mean by this?


And also, doug, thanks for clearing that thing up with the sprue. Is the sprue the only way to get the molten metal into the cast? Kind of like a 'tunnel' for it to go through? Like I said earlier, its very hard for me to understand whats being written in the book,despite going over it over and over. I wish it would just 'click' in my head and I would understand it better. I'm going to start saving up money for next year so I can fly to colorado and take that class on counterfeit detection and alteration..

 

Highly recommended. I took that class at ANA this year, taught by Brian Silliman. We also studied grading and conservation.

 

Heh, 900 fine! I took that class too (I Took the Grading, Conservation and authentication class with Brian Silliman last year)

The counterfeit detection and alteration class was only 1 day. What I'm talking about is the summer semininar held every year at the ANA headquarters, in colorado springs. They have like a 28 hour (!!) 2 week counterfeit detection class. I'm going to have to really save up alot of money to fly over there, hopefully by next year.

 

Just got caught up with this thread. Thanks for posting these great pics Matt. If these were in another thread with lesser quality pics, I'm sure most everyone would believe these to be real. No doubt.

On the $10 coin.... Is the center of the zero in 1910 sunken in? That's always a big red flag to look for and it appears to be on that coin. That alone can give it away.


BTW, to me these are scary good. They don't have many of the lesser features to look for let alone anything that's very obvious. Especially on an online photo.

 

Matt

This is a solid thread that is both interesting and informative. I have always stayed away from gold, and this thread, including the detailed comments of Doug, Goldcoinlover and others, confirms that I would have to do a LOT of reading before I would even think about wading into those waters.

Fine job.

 

Even though I was able to spot a few things on them, i agree with you. These counterfeits are so good that it makes me question my skills...I thought I would be able to spot most counterfeits but after looking at these I've realized I have to be MUCH more careful, especially on the indians.

It makes me wonder also, how many dealers actually have fake gold, if this many counterfeits out of geniune pieces are fake. I talked to my local coin dealer at Xavier coins and he said $3 pieces were hard for him to authenticate as well. I don't know, but I doubt he has as much skill as Matt.

 

I digged through some of my notes on authentication. It seems that coins struck from a new set of counterefiters dies often produce coins that are too prooflike, or PL. I think this may explain the almost proof nature of the coin. A later die state would look better.

Also, looking through Bill Fivaz book, I notice almost all of the counterfeit $10's indians are PL..which is odd. Maybe there is a trend going on there?

 

Here is one I came across today. The back looks good... really good... The obverse is lightly pitted and weakly defined.

IMO this one has a good chance of being real and I cant find any depressions or re cutting. But I wanted to post it as a possibile counterfiet and see what some others thought.