I had dinner with Bill, the Collector of Old Stuff. ("I just bought a Polish shako on ebay.’) He is now in the market for a shekel from the time of Jesus.
I mentioned that it would quite easy to recreate such a coin in vast numbers, recreating the old tools, metals and whatnot. Perfect copies.
He took exception, saying it would be impossible to pass off such a copy to an expert. (Not that he is an expert.)
Given the lack of quality control in 8BC, given the huge number of these things out there, given The long period of time these were produced, I maintain that such a perfect counterfeit could be easily and cheaply made.
Visually and tactily, for a coin I imagine that the main issues would be the state of the coin (i.e. rust, wear, and such) and the quality of the metal (a coin made from modern metal would probably be of higher quality.)
Other than that, I imagine you would need to do chemical tests. (Carbon dating, an analysis of the contents and quality of the metal, etc.)
First you have to get metallurgical information on the entire series of shekel coins in circulation at the beginning of the first millennium, and a fairly broad sample (at least good photographic images) of known genuine examples. You also have to do a lot of reading up on how to tell if they are genuine.
But there is one thing, and it is almost undefeatable for modern copies of very ancient artifacts. The modern ones are radioactive. You cannot get materials that are not more radioactive than the same materials made before 1945. The difference is small, but measurable. And the measurement is entirely damning in the matter of age of materials. So, you have to get samples with the same metallurgical content, but made before the twentieth century, and keep them isolated during your counterfeiting process.
What are shekels made of? (I don’t think gold, so the matter of age related corrosion is also critical.) Given that you are willing to have a “poor” condition shekel, rather than an “excellent” condition shekel, wear alone can be used for most of the age approximation. If you want a fake shekel that might be believed to have been found by Peter, in the mouth of a fish, you are going to need provenance. Where did you get this ancient shekel? If your story is good enough, you could get yourself arrested for illegal dealing in antiquities. Without it, it is an unknown object of doubtful provenance, and a mere curiosity among collectors.
Best bet is to bribe a European of noble ancestry to put your shekel into a group of genuine articles of historic age, and buy the lot from him. Now you claim the shekel was believed by the family to be a “holy relic” brought from the Crusades in 1100 or so AD, and reputed to be Peter’s Shekel by the family history. Now all you have to do is bribe a nuclear lab into dating it, and find it to be first millennium, and therefore possibly genuine.
Even never claiming it to be unassailably first century, you can probably get a half million for it from collectors. But it is going to cost you ten thousand or so in production costs, and bribes, and when those folks hear about the price, you may get a comeback.
Bill (the Collector of Old Stuff) says he is looking to spend USD900 for a good example. They are made of silver, I think.
The radioactivity thing is easy to beat. We will make our copies out of pre-1945 silver. No problem. Or for that matter we can refine our own silver ore. As long as we do not use post-1945 scrap we should be OK.
We will then slip them into the stream of genuine coins. As I mentioned, thousands of them exist.
At USD900 a pop, the project would pay for overhead (say $10K) pretty quickly and then we can buy a headquarters in an extinct volcano.
Beware of unscrupulous real estate agents. Sometimes they’ll mask active fumaroles and small lava lakes with a few dumptruck loads of gravel. It’ll look fine for a month or two, but then you’ve got real problems.
As I recall, all metal objects created since 1945 have trace amounts of radioactivity from exposure to the atmosphere. A metal object made prior to 1945 would have surface radioactivity traces but no internal traces.
But testing this is very difficult. First off, you have to get a sample form the core of the object being tested without damaging the object or exposing it to the atmosphere. Second, you have to have testing tools that are not themsleves contaminated by the same radioactive traces you’re testing for.
The source for high-grade non-contaminated steel? The German High Seas Fleet. Following the end of World War I, the German fleet was interned in Scotland. When the German officers suspected their ships were going to be turned over to the allies, they sailed them out to the North Sea and sank them. There are therefore thousands of tons of steel armor in the North Sea that haven’t been exposed to the Earth’s atmosphere since 1919.
Atmospheric fallout from above-ground nuclear testing. It contaminates metal that is smelted from ore or scrap. Some scientists have used metal salvaged from old sunken ships for experiments that are sensitive to small amounts of radioactive contamination.
No no, I mean as an example of the sort of dating test that can be done in a lab. Certainly there are ways around it, but when you get down to it, forgery tests have no real purpose beyond being able to detect a false beyond an amount to make it monetarily infeasible to make the copy.
My basic feeling about these things is that for most categories of object, it just isn’t worth it. $900 sounds like a lot, but think of the tooling and the antique silver you need just to produce a single example. So of course you don’t produce just one, you produce a number, and necessarily they all come out identical – which is suspicious, because suddenly there’s this new supply of coins in the market, which, on microscopic analysis, are shown to be identical with each other, but don’t match any other known examples.
Very few things are worth forging, because you need a good alignment between the tools, the materials, the abilities of the forger, and the economics of the market. That’s why alteration is much more an issue than forgery – you take an object that may already be of the period, and change a few of its characteristics to make it more valuable. For instance, with a painting, you take a genuine vintage painting and change nothing more than the signature – relatively easy, the painting is still 99.9% genuine, etc.
I’m kind of proud of myself as this is my first request for a cite. Sorry, but you knew it was coming. I just can’t imagine that all the materials on Earth, even underground, are now contaminated with radioactive materials. Are you saying that the materials are contaminated by uranium and other radioactive materials? Or are you suggesting that the materials (say, silver) now have a higher percentage of radioactive isotopes? Or is it something else, like all silver is just more radioactive now, for some reason or another?
Now I just feel like a fool.
But its not my fault, really! My computer got slow for a while and didn’t post this until after my questions had already been answered. So, everybody, thanks for clearing up my little misunderstanding with the radioactivity. I guess fallout makes sense, as I’m sure there’s plenty of air in just about any smelting facility.
But now I ask: wouldn’t it be possible to forge this coin simply by smelting your own silver in a sterile, or airless, environment? Or would this ruin the whole idea of forging an antique, since they obviously didn’t have such sterile environments to make the original coins?