An interesting and probably quite early Danubian horse
rider lead plaque from the Danubian Rider mystery cult - so called because the
names of deities associated with this Roman-period religion are unknown and
artefacts are identified by a pair of horsemen flanking a female deity and
accompanied by other distinctive iconographic elements.

Intact.

64mm.

Probably early 3rd century

These plaques show a complex iconography of divine
figures and Mithraic symbols, thought to be associated with Thracian or Dacian
beliefs of the Lower Danube region. Presiding over the whole scene is Sol
Invictus (the invincible sun-god) in a quadriga (four-horse chariot). His cult
originated in the Near East and gained increasing influence under imperial
patronage during the third century A.D. The state worship of Sol was only
supplanted by Constantine's adoption of Christianity in 312 A.D.

Although there are few hard facts about this cult and
almost nothing written has survived, it is possible to suggest interpretations
for much of the imagery by reference to contemporaneous religious activity
within the Roman Empire during the second and third centuries AD.

See  here and here for some
more info:

antoninus writes:

I have always regarded these circular examples as the earliest examples of the plaque culture.  They are styled upon early hand mirrors and were deliberately so in the tradition that you could not look directly upon a deity - just as Perseus could not look at the Gorgon!!   They are obscure to the uninitiated and few clues are given regarding the rituals, unlike the later square examples with separated fields and lots of graphic detail.

Here, the central goddess holds a rope across her waist, unlike other examples in which she holds the horses by the reins.   The reins may double for the rope?

All the usual ritual objects are present, a lion, a cockerel, a twin handled wine cup.   These represent the ancient three seasons of the year.   The snakes encompass the goddess with eternity and the equestrians flanking her are NOT the Dioscuri as some believe, but the Sun and Moon - Apollo and Artemis.  ( This comes from a study of later plaques.)  As I mentioned, these early plaques gave little away!!   In my view the earlier types could have predated their successors by as much as a century and might be dated to the end of the first century.