If your coin shares a die with an obvious fourre, it is probably a fourre. Your coin is almost certainly not tooled in my opinion looking at your photos and other die linked coins. I suggest you measure the specific gravity to confirm. It's quite simple to do, all you need is a gram scale (accurate to 1/100 g), a cup of water and a piece of thread. You can search youtube for SG techniques. Accuracy will not be precise but will be close enough to determine if the coin is mostly copper or mostly silver. repeat the process and record several attempts. Measure other denarii that you are pretty sure are silver as test samples.
Hey, even I managed to do a specific gravity test on a suspected Roman Republican fourree, and I'm a technological incompetent as well as something of a klutz -- you should have seen me trying to tie a piece of thread around the coin so it didn't fall out! I found these instructions easy to follow: http://coinsblog.ws/2016/06/detecting-counterfeits-specific-gravity.html. The one piece of equipment you'll need to make proper measurements is a digital scale that measures in 100ths of a gram rather than only 10ths of a gram. And here's a table I found listing the specific gravities of silver, copper, and alloys with various percentages of silver in a silver-copper alloy: 100% silver 10.49 100% copper 8.49 98% silver 10.45 90% silver 10.31 83.5% silver 10.20 75% silver 10.05 50% silver 9.65 40% silver 9.527 30% silver 9.37 20% silver 9.234
Here I am, back with some news. I made the specific gravity test and the result leans toward the Nero denarius being a fourree Its specific gravity is of 8.97, while I got 10.00 with the Domitian below and 10.67 with the Augustus That said the layer must be kind of thick : I've examined the coin again and again and don't see any sign of a core pointing its nose through it Just for the fun of it, the guy who intended to buy the coin before all that mess started, has made a superposition of different pictures (i.e. mine, CGB's and Elsen's) showing perfectly the die matches As stated by Doug, because I'm in France and wouldn't want to sending it to the USA with the Covid situation Anyway, thanks to everybody for their contributions, it's the kind of sleuthing which makes this hobby so enjoyable....even at the cost of a Nero denarius Q
I’m sorry the denarius is likely not what you thought it was @Cucumbor but if it is any consolation that is one heck of a nice fourree!
Read this thread with interest. I know SGs are often dismissed by some, as you get different results on different tests (without really accurate scales and equipment etc). One thing I will say however, although you can't trust an SG to give you an precise result, you can trust it to give you an approximate result. A result of below 9 tells you definitively it does not contain any decent amount of silver. It doesn't tell you what it is, but it tells you what it's not. Well done on the sleuthing @Cucumbor
So, it's a fourree... Well, on the one hand, too bad its not a proper, genuine coin. On the other hand that does exclude that it is a modern fake, right? I'm not quite sure if I should now eat my baret silently in the corner...
This leaves the question of the status of the other coins of the type sold as solid. Are all fourrees? Was the whole issue debased so the others would test with low specific gravity?
Perfectly right. Although the mesure isn't accurate, one can assume the error to be the same when all the meures are made the same day in the same conditions. I found 10.67 SG on the Augustus, meaning it would be more than 100% silver (that's the first fricken good news in this story ). Also I tested two modern 835/1000 silver coins which both gave the same reslult of 9,65 SG Thanks Well, it's up to you to keep your promise Q
Sorry your Nero turned out to be not what you bought it as, Q, but on the other hand, it's now one heckuva fourrée! And for still being able to (almost) pass off as the real deal almost 2,000 years later, definitely still a keeper, IMHO.