Severus Alexander, AE26 Tetrassarion of Tomis, Thrace. 12.23 gr.

AVT K M AVR CEV ALEXANDROC, Laureate and draped bust right, seen from behind.
MHTRO PONTOV TOMEWC, Hygieia standing right, feeding serpent in 
arms. Delta (denomination) in right field. 

Varbanov 5361 var (delta left); Moushmov 2156.

Varbanov does not list this reverse type with delta in
the right field.
With permission of cngcoins.com, Electronic Auction 228,
Feb. 2010, lot 212. Sold for $60.