I have some Denarii of the Roman Republic and their weight is close to four grams. I have one, an Apollo head of Piso Frugi, but the one of about 65 BC not the earlier one of about 90 BC. Its weight is 3.3 grams. Is this within the proper limits of the denarius of that period or does it represent something unusual? Thanks.
Most likely, yes they are fine. 3.3 is low, but I have an issue of C. Allius Bala from 92 BC which is barely over 3g, but I'm virtually certain is real and just an outlier. If you have suspicions of the low weight coin, post it and we'll take a look at it. Low weight could also indicate a fourree.
Unfortunately my tech skills are those of Ancient times and I have no idea of how to post images. However it is not a fourree as somebody took a little bite out of the rim to expose the metal below the surface. It appears to be a struck coin as the flan is flattened and thin at one end and the flan also has a small irregular crack running along both sides of the coin.
Could be a fourree, a fake, or it could simply be a coin that lost weight due to leeching. Some coins, especially random ground finds, can lose weight due to the metal being leeched out over the years by water in the soil. Usually they will feel brittle and a little porous.
Crawford in Roman Republican Coinage gives weight standards and some average weights. An article in The Celator gave average weights and standard deviations. (I have found the article online in the past, but did not find it today.) When I buy a coin on line, I look for similar examples online (CNG, Sixbid, V-Coins & the British Museum and others) and calculate the average weight, standard deviation, max & min weights. If the coin is outside those norma, I worry about the coin. The weight of Roman Republican denarii started near 4.5 grams per coin in 211 BC and dropped to about 4 grams by 200 BC. The average weight continued to drop, but increased near the end of the RR period (27 BC) to near 4 grams. I would guess that 3.3 is low for Piso Frugi's coins, but within 2 or 3 standard deviations. Piso minted lots of denarii and some low weights is expected.
I have most Celators, (in fact duplicates of many years). If you know the issue number I could look it up.
Many coins and certainly the Republicans were issued so many to a weight of silver. It was important to them that they got 72 (for example) coins from a pound of silver but they lost little sleep over each coin being exactly the same as every other coin. This is termed al marco system of weight standards.
