Overfarvet snerleglas, ca 1880.Height 12. 5 cm. The glass has a nice manganese color in daylight it's hard to capture in photos. Snerle glass first appears in Danish glass catalogs in 1867 and disappears during the early 1900s. To remove the grayish tone that glass could have, manganese was often added. This helped to clean the mass and give the glass a whiter color. Sometimes the glass mass was overdyed and then took on a purple or pink hue, like this glass.