Opaline, also known as opal glass, was made in a variety of colors. White, green, and blue being the most popular-colors. Opaline glass typically had a matte surface and a lack of transparency. Most pieces were further enhanced with gilded ormolu or painted. It was a popular 1800s to early 1900s European glassware. Opaline glass has become very collectible and pieces in good vintage condition are becoming rarer to find.