Interesting coin due to the fact that it was minted for Severina. Her coins appear in circulation relatively rarely.
In 274 AD Aurelian began a great monetary reform and created a new antoninianus or aurelianus with the XXI mark, containing only about 5% silver, hence the equivalence: 1 piece of pure silver = 20 aurelians.
Very well preserved specimen with a lot of silvering.
Roman Imperial
Aurelian (270-275), Billon Antoninianus 274-275, Antioch mint
Obverse: laureate and cuirassed bust right
SEVERINA AVG
Reverse: Concordia standing left, holding two standarts, XXI in exergue
CONCORDIAE MILITVM
Weight 3.82 g
Severina was awarded the title of Augusta in 274 AD. She survived her husband Aurelian, murdered in a military plot. There was a three-month interregnum, during which Severina was able to continue to regulate the current affairs of the Empire through the Senate. Severine's coins are much rarer compared to her husband's coins, as they were minted in a very short period between the end of 274 AD, the date of the reform, and the date of Aurelian's death in 275 AD.
