I bought a 3/8th Shekel from Brutium, during Punic occupation, in electrum, 216 – 211 BC. I have posted the coin here, and on my blog - (http://rrdenarius.blogspot.com/). This post is to talk about estimating gold content by measuring SpGr. I have seen several articles on line about this technique (http://www.mdhtalk.org/faqs/sg.htm). My method is a bit different, but seems to work. The coin looks silver to me, but there is a significant difference in the SpGr (or density) of silver (10.5) and electrum (12.0 for coins in Jenkins & Lewis). My measurements say the coin is probably electrum. The coin. My method: I made 5 series of weight measurements. Weigh the coin dry. Use Teflon dental floss to tie the coin on a string. Fill a small cup with water Place the cup on a scale and zero the scale. Hold the coin in the cup, under water, without letting it touch the sides. SpGr = Wt of coin in air / Wt of coin in water To “confirm” my test, I tested one buffalo nickel, two Roman Republican denarii and one silver nugget. The results are: SpGr of my coin = 11.0 - 12.1. This corresponds to 10% - 30% gold. The results vary a lot with the small weight in water. I do not know how to post a table here. If you want to see the results, go to my blog. Post any electrum coins you have. Let me know if you have measured SpGr on any of your coins.
I asked a professor of Geology at the university of Colorado to do a test on a piece that broke off around the edge of the indention near the top of this. He said it was in the low 7's. He did mention the piece was a bit small to test with, but I assume it is in the ballpark?
Your Bruttium was a War issue under Hannibal's occupation. Curious. Perhaps this was a later issue with him skimping gold when combined with the silver. If it were natural EL, perhaps it was a diluted ore. This is the only Electrum that I have now, and no, it is not of any of the Punic Wars. Rather, it was minted during the heady days of the Carthage Empire prior to any of the Punic Wars: Carthage Zeugitana 350-270 BCE EL Dekadrachm-Stater 18.5mm 7.27g Tanit Horse 3 pellets in ex MAA 10 SNG COP137 SNG Sicily 975 I have not performed a SG Test on this yet. However, in-hand, it clearly has a very gold look to it.
Very interesting @rrdenarius. I never thought of measuring the SpGr, good idea, thanks for sharing! I especially appreciate your photos, I think replicating your method would be easy.
Nice bit of scientific detective work @rrdenarius . Not that style is dispositive evidence of date, but certain style elements of @rrdenarius coin remind me of. the latest iteration of AR Quadrigati-didrachms of the Roman Republic. Those Quadrigati would have been struck and circulating circa 214-212 BCE, just before introduction of the denarius coinage. In particular, the horizontal hairs at the top of the Janiform head and the low angle of the quadriga are consistent with the Roman quadrigati of this 214-212 BCE time frame, which the Carthaginians were likely copying. Here's an example of the late Quadrigati that I'm talking about (not mine):
Just kidding, that pretty cool @rrdenarius ! Neat specific gravity experiment on your coin! I pieced your table together and made a pic out of it, it didn't come perfect but it looks ok.
