2017 Philadelphia Minted Lincoln Shield Cent Struck On Bronze Planchet

Neither you nor PCGS have provided any information regarding beam strength or depth of penetration. Considering that PCGS has slabbed many cents struck on foreign copper-plated zinc planchets as "copper", I have no confidence in their determinations.

The majority of pennies weigh \(3\text{\ g}\)-\(3.1\text{\ g}\), but there are also numerous pennies that weigh \(3.2\text{\ g}\) or even \(3.3\text{\ g}\). Conversely, some weigh between \(2.8\text{\ g}\) and \(2.9\text{\ g}\), which is still within the range of what is considered acceptable. There are also tests you can conduct to determine the density of an object made of a particular material. Nonetheless, the most crucial test that determined the outcome was X-ray Fluorescence (XRF) testing. There is no way to manipulate that test; if there were, people would be exploiting it to pass coins through grading companies. Furthermore, Jon Sullivan—a very knowledgeable and professional individual—certified the coin himself and provided his recommendation. 

It doesn't specifically say what "beam strength" is being utilized but I think it's just a standard calibration for the machine in general the adds reassurance and effectiveness.

The fact that matter is, these machines used to conduct metallurgic testing are worth their weight in gold, figuratively and literally. Lots of precious metal dealers, whether it be jewelry or simply precious metal exchanges, utilize and rely upon these machines, and yes, they are non-intrusive. In some situations that's necessary, when you have a high-end gold coin that's worth hundreds, if not millions, of dollars. This is what they turn to. And I'm sure people try their best to pass off fake coins coated in gold.

And yes, there are some videos where people are showing that these machines are 100% accurate, but it's just usually a video promoting another one of these machines. I just think that there was maybe a calibration issue or something was being done incorrectly. I don't think there is a beam strength, but I don't know. I don't own one of these machines. I don't really know anything about them other than what information is available. But I do know that multiple people utilize these machines to conduct very serious business with very serious money.

In fact, the matter is, I found a penny that exchanged multiple hands, had multiple tests completed by professionals who do this every single day, who see hundreds, if not thousands, of fake coins. And the fact the matter is, I don't know what it's worth, but the fact of the matter is, this is an error coin. An individual who is capable of producing such an elaborate fake wouldn't be wasting their time and effort on a single cent, but rather items of gold, probably not even silver, because it's gold, an extreme amount of value as is. Imagine if you could produce fake gold coins that could pass these elemental tests as well as the professionals who know even the smallest indifference of the dies to produce coins in general. One condition, 1909-S VDB MS condition, as well as the 1916-D, the 1914-D. One person, take Henning nickels for instance. I found two of those in one month. I gave my brother a 1944 and I sold a 1939. I haven't found another one since, but fact the matter is...

Oh yeah, there's many, many people—thousands of people—who say that they have this or they have that, 'I have a gold penny,' yada yada yada. But there was no test performed, and we're not just talking about a ping test. We're talking about a test that is designed for applications that are extremely important. You can't fake it; you can't manipulate it in any way, shape or form. They are using literal radiation for elemental analysis, and if it could be manipulated or cheated in such a way, then the whole numismatic community would have more skepticism for a numerical grade that changes with every submission rather than a precise radiation test."

I doubt that makes much difference. You can blast more X-rays at a surface, effectively increasing amplitude, but you would need higher energy (meaning higher frequency) X-rays to penetrate deeper. The stuff I've read online about XRF technology suggests that it reaches a few hundred microns (or a few 0.1mm increments) into a dense metal surface like gold, silver, copper, lead. A U.S. cent is about 1.5mm thick. Could it reach the interior? On paper, maybe. I wouldn't bet $10000+ of my own money on that assumption. I would want to see a battery of tests on a control group, first, with multiple variations.

However—and it's a big however—most measurement techniques that rely on EM reflection are probably heavily biased towards the surface if the metal structure is non-uniform. I think it's a bit concerning that the planchet doesn't read as the proper pre-1982 copper alloy composition, because a vintage planchet would be a uniform metal alloy from the surface straight through the core.

Having been involved in testing semiconductors, I would have imagined that they would have run a series of tests on that coin. Specific gravity is the first one that comes to mind, followed by mechanical parameters like diameter and thickness, and then conductivity and electrical tests.

A specific gravity test would arguably be more useful in these circumstances as zinc has a significantly lower density than copper. Even a heavy layer of copper plating wouldn't obscure this.

Yeah, a density test could be possible, but not as accurate as x-ray fluorescence, not by any stretch. Tungsten is used in the manufacture of counterfeit gold coins, and as far as density goes, from what I understand, it's identical if not almost identical.