Andrew - I'm not sure I follow your logic. Your archaeologists of 3012 would surely conclude that the banknotes represented what was in circulation, since banknotes have no intrinsic value and they were all marked $100. If they
still had banknotes or coins at that time (or even if they didn't) they would surely realise that fresh, worn, old or new currency would happily circulate together.
I don't think anyone has proposed, based on
hoard evidence, that in the
Roman era coins circulated by
weight, have they? Carradice's
work on
Flavian coinage is instructive. He shows that Domitian's high
quality denarius, issued 82-85 AD, rapidly disappears from
hoards, whereas
his later
denarii, issued 85-86 AD, continued to appear in
hoards in large quantities until the time of
Septimius Severus. We must surely assume that the 'good' coins also disappeared from circulation for
good, or else they would have gone back into later
hoards. A
bit of a
chicken and
egg question, but I think that
hoards did mirror what was in circulation.
I believe it is a mistake to think of hoarding as a one way journey for coins. We have that impression because the coins in
hoards we find today obviously have never been returned to circulation Using a modern analogy! businesses have bank accounts into which
money flows in and out according to business cycles. Clearly we can never know what ancient
hoards were used for, but a
hoard which changed it's composition over time would mirror circulation.
Most British
hoards of imperial
Romans have coins that cover quite a long time period, sometimes over 100 years. Richard
Abdy shows that the distribution of coins over time follows a skewed
bell curve. Given that coins took some years to come into full circulation (twenty or thirty years sometimes in the case of
Britain), the high point of the curve would be some years previous, a low point where the newest coins have only just come into circulation and a tapering low point where earlier coins are present but diminishing. Again this points the idea that composition of
hoards followed what was in circulation. While hoarders may have been selective to a certain extent, the coinage was fiduciary so there was no actual profit in selecting 'good' coins, just a feel-good factor.