Ancient Roman silver Siliqua of Constantius II / Antioch

This is a good ancient Roman silver Siliqua of emperor Constantius II struck between 355-361 AD.

Obverse: D N CONSTANTIVS PF AVG "Our Lord Constantius Pious Fortunate August" - pearl-diademed, draped, cuirassed bust right

Reverse: VOTIS XXX MVLTIS XXXX "vows (prayers) on the Thirtieth anniversary (of the emperor's rule), and for his (anticipated) Fortieth anniversary" in four lines within the wreath. 

CULTURE: ROMAN

DENOMINATION: Siliqua

MATERIAL: Silver

DATE: 337 - 361 AD. (this coin was minted between 355 - 361 AD)

MINTMARK: ANT (Antioch, Turkey)

SIZE: 18mm dia

WEIGHT: 1.88 grams

ATTRIBUTION: RIC VIII 108

PROVENANCE: Private collection. Cologne, Germany.