Roman Pale Green Mould-Blown Glass Janiform or "Janus Head" Flask

Pale Green Mould-Blown Roman Glass Janiform or "Janus Head" Flask
Probably from Sidon, Phoenicia.
Circa 1st-2nd Century A.D.  
Dimensions: 8.1 cm tall

Provenance:
An Ex Cambridge Gentleman’s Collection. Acquired before 1970.

A translucent ancient Roman green glass, mould-blown flask with a cylindrical neck with everted flared rim with folded lip. A fine, intact example with some encrusted deposits and age acquired iridescence.

The flask is of a type with faces to either side, representing the Roman god Janus. 

Notes:
For a similar flask see Lot 161, Christie's South Kensington, Sale of Antiquities, 14th Apr 2011