It's fascinating to me that the coins dated all the way from 200 AD to 400 AD. Finding a US cent from even 100 years ago is a surprise and delight these days, and I imagine it's similar throughout the world. But somehow, 1600 years ago, somebody had a hoard of coins that were up to 200 years old.
There is Gresham's law in action there. People would hoard more valuable coins (with higher precious metal content) and use less valuable coins in daily circulation.
Given that metal does not age that much, 200 year old coins in hoards aren't that surprising.
Until comparatively recently, at scale from 0BCE Gold was exchanged and hoarded. It had specific value, the world was on the gold standard. Coins represented unit value but also inherent value by weight and old coins could be better or worse depending on dilution of the date of minting and so were either valuable because heavy with gold or valuable to cheat because light, and so Gresham's law applied (their use value exceeded their gold value if you can find a fool to take them)
Before decimalisation as a kid I'd handled Georgian pennies and halfpennies in Britain doing shopping, some rare sixpences in circulation were silver and you could get guinea coins at a premium from your bank.
Most people expected late Victorian as normal, young Victorian as less common and anything older as remarkable. So that's 100-150 years of coins in circulation at their nominal face value, under moderate inflation since 1800 with the Napoleonic wars and at least five significant slumps before ww2.
I'm talking 1960s after brettan-woods, and at the same time lire in italy was deflating and we got lollies as change from bus conductors. If Europe hadnt been beset by fire since 1848/1871/1914/1939 I think circulating European currencies would have spanned 2 centuries too like Britain: most of them had postwar currency "reinvention" and I was also handling old and new francs (10:1 exchange equivalency IIRC)
Fascinating. I bought an assignat as a gift, a relic of belief in fiat from 1789. I did wonder which successor French state would honour it. (Obv. None)
You notice how much more than face value they have in some circumstances. After 1919 if circulating not valuable but even 1969 mint or uncirculated is worth significantly more than face value.