What Is Opal Glass?

   Opal glass has been around a long time, it was first manufactured by glass blowing houses in 16th century Venice! Opal glass is made by adding opacifiers to the melt. The particles in the opacifiers scatter light via the Tyndal Scattering Mechanism. The way light is scattered and the secondary colors produced depend on the size of the particles in the opacifiers added to the melt. Modern opal glass typically has the appearance of opaque white glass, but has also been manufactured historically in pink, blue, yellow, brown and black. When the thinner parts of the glass, like around the neck finish are viewed in the light they can appear slightly blue or sometimes orange, like in the photo shown above. This is the effect of the Tyndal Scattering Mechanism.

    Opal glass gets it’s white color from the addition of bone ash, tin dioxide, or antimony compounds, which are also sometimes added to ceramic glazes to produce a milky white color. Opal glass is also sometimes also referred to as Milk glass, although Milk Glass is a relatively new term.

    Opal glass has been used throughout the ages for everything from lamps to marquees to clock faces to tableware and more recently, personal care containers.