here is a nice example in the current Holyland Auction-- e-Auction 5
Mid 4th century AD. AE 16 mm. Alexandria mint.
Weight 1.75 gm.
Obverse: DEO SANCTO SERAPIDI, draped bust of Serapis right, wearing modius.
Reverse: DEO SANCTO NILO, Nilus reclining left, holding reed and cornucopia, ALE in ex.
Near extremely fine. Rare.
Vagi 2959.
Estimate: 1000$