Roman glass production developed from Hellenistic technical traditions, initially concentrating on the production of intensely coloured cast glass vessels.
However during the 1st c. AD, the industry underwent rapid technical growth that saw the introduction of glass blowing and the dominance of colourless glasses. By the end of the 1st c. AD, large scale manufacturing resulted in the establishment of glass as a commonly available material in the Roman Empire, and one which also had technically very difficult specialized types of luxury glass.
Cage cup, 4th c. AD, Cologne. (c) Vassil 
Enamelled glass depicting a gladiator, 1st-2nd c. AD, found at Begram, Afghanistan. 
Glass perfume bottle, 1st c. BC. Metropolitan Museum of Arts. 
Ribbed bowl of mosaic glass. Metropolitan Museum of Art. 
Lycurgus Cup, 4th c. AD. British Museum. (c) Johnbod
Gold Glass
Gold glass is a luxury form of glass where a decorative design in gold leaf is fused between two layers of glass.
First found in Hellenistic Greece, it is especially characteristic of the Roman glass of the Roman Empire in the 3rd-4th c. AD.
Gold glass medallion of a youth named Gennadios, who was “most accomplished in the musical arts”, from Alexandria, c. 250–300 AD. Metropolitan Museum of Art. 
Gladiator in gold glass. (c) Johnbod 
Portrait of a couple, 3rd c. AD.
Digital Maps of the Ancient World 