I think
VIRT AVGG occurs at
Rome only for Septimius: see first picture below (from
Wildwinds). This
type passes from L SEPT
SEV AVG IMP XI
PART MAX (
rare) to SEVERVS
AVG PART MAX, so it must have been introduced in c.
spring 199 and may have been struck for most of the rest of the year.
Virtus stands left, seen from the
side, right
leg advanced and slightly bent, holding
Victory out before her and spear and
shield resting on ground behind her
Caracalla as ANTONINVS
AVGVSTVS has two
VIRT AVGG types on new-style
Eastern denarii ("
Laodicea").
One
type is exactly like Septimius' at
Rome, except that
Virtus places her right foot on a helmet. She is seen from
side and holds spear and
shield behind her as at
Rome for Septimius. This
type is
rare; my only plaster
cast is of a coin in
Vienna and I don't recall offhand ever having seen another specimen.
Caracalla's second new-style
VIRT AVGG type is simplified and standardized:
Virtus now stands left in the normal pose,
weight on right not left
leg, and her
shield is omitted, allowing her to grasp the spear with raised rather than lowered left hand. Sometimes the
Victory she holds stands on a globe, a slight Eastern variation of the
type. See
Wildwinds picture below.
It seems likely that the Eastern
mint copied this
type from
Rome, but struck it for
Caracalla not Septimius. Caracalla's first
type closely copies the
Roman model of Septimius, with the addition of a helmet for
Virtus to step on, but very soon the
type was slightly altered and simplified for the
bulk of the issue.