Short answers, pulled from the story.
Roman glass was made primarily from silica (sand) and soda, with natron serving as the flux to lower the melting point of the silica. The main source of natron during the Roman period was Wadi El Natrun in Egypt. Lime, entering naturally through calcareous particles in beach sand, acted as a stabiliser.
Glass blowing was introduced during the 1st century AD. By the middle to late 1st century AD, older casting and core-forming techniques had been largely abandoned in favour of blowing, which produced thinner walls, required less raw material, and was significantly faster than earlier methods.
Roman glass reached the Han Empire of China and the royal tombs of the Silla Kingdom in Korea. The first Roman glass found in China came from an early 1st-century BC tomb at Guangzhou, carried via the South China Sea. The set of objects found in Gyeonggi Province, Korea, is designated a National Treasure.
During the last thirty years of the 1st century AD, strong colours disappeared rapidly from the market, replaced by aqua and true colourless glass. Pliny's Natural History states that the most highly valued glass closely resembled rock crystal, suggesting colourless glass was fashionable either as a material in its own right or as an imitation of prized rock crystal.
Gold glass, also called gold sandwich glass, is a technique that fixes a layer of gold leaf with a design between two fused layers of glass. Approximately 500 examples survive, and the great majority are roundels pressed into the mortar of graves in the Catacombs of Rome. Most date to the 4th century and depict Christian subjects.
The Romano-Germanic Museum in Cologne holds the world's largest collection of Roman glass vessels from the 1st to 4th centuries, with more than 4,000 complete pieces. The collection includes the famous Cologne cage cup from the 4th century and examples of the distinctive Cologne nubs style.