I bought this from a V-coins dealer who described it as a "hybrid mule type with reverse of Julia Domna." However, he erred in saying its reverse type is a denarius of Julia Domna. It isn't; it has a reverse type of Julia Mamaea. I presume it's an ancient counterfeit -- it's underweight and doesn't quite match any official issue. Yet, there's no indication of a base metal core. I can find no other example of this coin online and I've looked at acsearch info, Coin Archives, Wildwinds, The Coin Project, OCRE, and v-coins. It is not in Sear, BMCRE or CRE. Sorry about the photo; the coin itself has frosty and porous surfaces, as if it were harshly cleaned by acid, and it doesn't photograph well. I'd love to hear your comments about this one: Julia Maesa, AD 218-225. Roman (counterfeit?) AR denarius, 2.35 g, 19.2 mm, 5 h. Roman mint style Obv: IVLIA MAESA AVG, bare-headed and draped bust, right. Rev: VENVS VICTRIX, Venus standing left, holding helmet and scepter, shield at her feet (reverse type of Julia Mamaea, RIC 358). Refs: Similar to RIC 275 and Cohen 52. Here's the listing in RIC, but the reverse description doesn't quite match: Rather, the reverse type seems to be this one of Julia Mamaea, RIC 358: You'll note the footnote in RIC speaks of an eastern issue where Venus holds a statuette. This undoubtedly refers to a coin such as this one, sold by Naumann (Auction 69, lot 399, Sept. 2, 2018): I suspect that Cohen 52 (which is cited by RIC as 275), is actually this coin, but the reverse device was unclear and Cohen, expecting to see Venus Victrix holding a helmet, described it as a helmet: BMC lists a large variety of hybrids mixing obverses and reverses of Julia Domna, Julia Maesa, and Julia Soamias, but this isn't on their list. The BMC does have a denarius of eastern mintage (purchased from Curtis Clay, interestingly enough), which depicts Venus standing left, holding a vertical scepter in her right hand and cornucopia in her left one: So, my coin doesn't appear to match any official issue and appears to be a mule combining the obverse of Julia Maesa with a reverse type of her daughter, Julia Mamaea. It's almost certainly a counterfeit, but doesn't seem to be fouree.
Limes denarii are usually base-metal versions of official issues and were probably not counterfeits, but officially issued under certain circumstances. This one, I think, is an ancient forgery, but I don't see a base metal core to suspect a fourrée. That's what puzzles me.
Perhaps my use of the term "limes" was imprecise. I meant to suggest that it might have been issued by an unofficial mint under local authority to facilitate trade in a boundary region.
I just bought this imitative Julia Soaemias. There are only three official reverse types, so it’s nice to be able to add a fourth. A certain new Canadian auction house is offering one of these.
My opinion isn't worth much, but could it be a debased silver (maybe ~20-40%) counterfeit? More expensive but probably faster than the fouree process. Or were they producing significantly debased official denarii already at that time? It looks like it was recovered from a chemically-saturated field or waterway which preferentially attacked the copper, leaving the coin rough eroded and porous. Or if it is good silver, a sulfur or sulfide-rich environment. My experience detecting and digging old dumps for antiques shows that in less than a century Sterling silver items (spoons etc.) can be eaten away by the chems concentrated in some areas. Not really relevant, but I hope you can get to to the bottom of the mystery!
I think the silver/copper ratios varied a bit from mint to mint. I have some denarii of Elagabalus that don't appear to be more than about 50% silver. Quality control was pretty poor around that time.
