Exhibit Antiques has dated this piece to the Before 1700 period.
An uncommon Roman glass unguentarium perfume bottle dating from the 2nd to 3rd century AD.
The rim is folded and finished at the furnace, a flaring lip is pulled to form a tapering neck and an angular blown body with a pontil scar to the slightly thickened base.

Date & Origin
Roman, Mid Imperial Empire, 2nd to 3rd century CE.
Condition
Intact. The exterior exhibits a stunning flaking patina layer and cream-to-brown natural staining. Iridescent surface and encrustation to parts.
Dimensions
Height: 11.5 cm
Diameter: 3.5 cm
Provenance
Bonhams, London - December 1999.
References
MET museum: https://www.metmuseum.org/art/collection/search/245213
Exhibit Antiques has dated this piece to the Before 1700 period.
Specialists in 18th & 19th century antique glass
You can view the stock and full dealer information on the Exhibit Antiques Profile Page