Minimum "Standard" Weight of Legionary Denarii

[Ken W2]

Full disclosure, this is a due diligence question about MA Legionary denarii, but a somewhat general one.  I know the weight of denarii ranged widely over the entire period of production, but here we're focusing on the Legionary denarii minted in only two years-- 32-31 BC.  It occurs to me that because these coins were minted in less than ideal conditions, perhaps even in mints moving with Antony's army, quality control probably was lacking at times and weights might vary widely even in such a short run.  What I'm particularly interested in is whether there is a minimum weight that should arouse suspicion, even if you were completely satisfied that all other characterics of the coin indicated genuiness ? I've looked at a lot of Legionaries over the last year and it appears that most weigh between 3.4 and 3.8 grams, perhaps with the most frequently occuring weight being 3.6 to 3.7 grams.  I have opened the "text" links for all Legionaries on Wildwinds (well over 100) and only three weigh less than 3 grams, coming in at 2.69, 2.75, 2.95 grams.  That's roughly 25% less than what the average appears to be.  Do weights that low suggest a fake, again, even though the coin otherwise appears genuine ?

Thanks in advance.

Ken     

[traveler]

It depends. According to Butcher, Antony's legionary denarii were struck to a lower weight and fineness as compared to Republican denarii. About 3.7g and 83% fine.

Theoretically a pristine looking coin weighing 3.1 grams or so might still be genuine, if we assume that all the base metals were leached out (0.83 * 3.7= 3.071).

However, and this complicates things. Antony's denarii were known in ancient times to be less pure, and consequently circulated for a long time. So they are often very well worn and will have lost weight. Between circulation induced weight loss and base metal leaching, it is very difficult to say what a minimum acceptable weight should be.

Examining the relevant coin images while considering the weight will probably be the best way to go.

[PMah]

As noted by traveler, much depends on the condition of the coin. I have some that are nearly worn to illegibity.  Although the average weight may be in the mid 3s, you can see on CRRO that there are quite a few museum specimens that are less than 3.0 g. 
   By my quick eyeball at CRRO, there are several specimens below 3.0 g in each of several of the many RRC 544 types. That's a higher ratio of lower weights that your observations from Wildwinds.  For example, I counted 3 out of about 41 just among 554/24 :
 http://numismatics.org/crro/id/rrc-544.24
(CRRO also automatically calculates the average of each type, which you can refine further if needed.)   
Wildwinds has a lot of examples from the coin market and might skew a bit towards less worn specimens.
   So, that under 3.0 g weight does not itself seem dispositive.