Here is a nice example of Constantine as Caesar with a rarer reverse type.
Constantine I
A.D. 307
28mm 12.3gm
FL VAL CONSTANTINVS NOB CAES; laureate head right.
GENIO AVGG ET CAESARVM NN; Genius stg. l., modius on head, naked but for chlamys over l. shoulder, r. holding patera (from which liquor flows), l. cornucopiae; in right field ✶.
In ex. K Γ
RIC VI Cyzicus 26b