From Wikipedia: Milk glass is an opaque or translucent milky white or colored glass, blown or pressed into a wide variety of shapes. First made in Venice in the 16th century, colors include blue, pink, yellow, brown, black, and the white that led to its popular name. 19th-century glass makers called milky white opaque glass “opal glass”. The name milk glass is relatively recent. The white color is achieved through the addition of an opacifier, e.g. tin dioxide or bone ash.
Visit: National Milk Glass Collectors Society (NMGCS)
Made into decorative dinnerware, lamps, vases, and costume jewelry, milk glass was highly popular during the fin de siecle. Pieces made for the wealthy of the Gilded Age are known for their delicacy and beauty in color and design, while Depression glass pieces of the 1930s and ’40s are less so. Milk glass has a considerable following of collectors. Glass makers continue to produce both original pieces and reproductions of popular collectible pieces and patterns.