The term "opaline" refers to a number of different styles of glassware.
In France, the term 'opaline' is used to refer to multiple types of glass, and not specifically antique colored crystal or semi-crystal, as is commonly thought, with 'opaline' often a mistakenly-given term referring to the color of a particular type of glass, rather than the age, origin or content of the glass.
19th century opaline glass
Opaline glass was produced throughout nearly the entirety of the 19th century, though it reached its peak of popularity during the reign of Napoleon III in the 1850s and 1860s. The glass is opaque or slightly translucent, and can appear either white or brightly colored in shades of green, blue, pink, black, lavender and yellow. The glass has a high lead content, which defines it as "demi-crystal" or semi-crystal. The primary influences on this style of glass were 16th century Venetian milk glass, and English white glass produced in 18th century Bristol.
Many different pieces were produced in opaline glass, including vases, bowls, cups, coupes, decanters, perfume bottles, boxes, clocks and other implements. Cities involved in the production included Le Creusot, Baccarat, and Saint-Louis, Réunion, as well as various locations in England.
All opaline glass is hand-blown and has a rough or polished pontil on the bottom. There are no seams and no machine engraving, and most opaline glass is not branded or signed. Many pieces of opaline glass are decorated with gilding. Some with handpainted flowers or birds. Several have bronze ormolu mounts, rims, hinges or holders.
Later opaline glass
In the 20th century, Italy began producing a similar type of glass, labelled 'opaline veritable'.
- Vincendeau, Christine. Les Opalines. (in French)
- Amic, Yolande. L'Opaline française au XIXe siècle. (in French)