Vandal Gold

[Rand]

1 hour ago, Tejas said:

However, if the tremissis is from Toulouse and the solidus is from Arles, is this enough to account for the difference?

I think so. They were also probably minted at different times and contexts. If the solidi had been minted during Theodoric's war, the Visigoths would have had gold and needed good money to pay for troops and supplies. 
The difference in the weight standard could have (partly) accounted for the difference in the gold fineness.

[Tejas]

Just playing devils advocate here, if these solidi were a short-lived issue that was linked to one historical event, how do you explain the existence of what seems like successive issues with a development of style?

Edited October 10 by Tejas

[Rand]

I do not think they were short-lived. I think the mint was active throughout the Anastasian period.

Arles was the capital of Provence, a very rich region at the time in its own right. Euric died in Arles in 484. It was possible that around that time, minting started (perhaps from your solidus) and was boosted soon by the Ostrhogotic war. Provinciales Galliarum was created by Theodoric in 511 and placed under the authority of ‘praetorian prefect’. Under Theodoric, the Gallic province had a status similar to Italy. Alres was its capital.

The 491-492 coins of Anastasius from ?Arles continued with a gradually evolving style (there is a very interesting die link). 

The below solidus from the Nomos auction was possibly minted during the siege of Geisalic in Arles in 507-508. I mentioned the idea in a private communication to a dealer, and somehow, my suggestion is virtually copied in French for a die-matched solidus auctioned by MDC (https://www.numisbids.com/n.php?p=lot&sid=8392&lot=577).

I believe that Arles mint came to real importance under Theodoric. This may be why the mint of Milan was closed around the same time (at least for gold coins). It is possible that part of the mint of Milan was relocated, explaining some overlap in styles, which makes attributions even more difficult.

There are a few solidi and tremisses that can be provisionally attributed to Arles throughout the Anastasian period. Still, the scarcity of individual varieties and lack of find records complicates the matter (my opinion changed more than once).

[Tejas]

The Visigothic king Euric resided in Arles around 476 and since we have no solidi attributed to the Visigoths in the name of Zeno, the attribution of the Zeno-imitations to this king and this mint seems very plausible. 

Indeed, we have Visigothic solidi in the name of Valentinian III and in the name of Justinian. I find it hard to believe that the mints under Visigothic rule would not produce any solidi in the intermitten period.

Your solidus above is spectacular.

Edited October 13 by Tejas