Glass float

Glass floats, glass fishing floats, or Japanese glass fishing floats are popular collectors' items. They were once used by fishermen in many parts of the world to keep their fishing nets, as well as longlines or droplines afloat.

Large groups of fishnets strung together, sometimes 50 miles (80 km) long, were set adrift in the ocean and supported near the surface by hollow glass balls or cylinders containing air to give them buoyancy. These glass floats are no longer used by fishermen, but many of them are still afloat in the world's oceans, primarily the Pacific. They have become a popular collectors' item for beachcombers and decorators. Replicas are now manufactured.

Norway, around 1840, was the first country to produce and use glass fishing floats. Many of them can still be found in local boathouses. Christopher Faye, a Norwegian merchant from Bergen, is credited with their invention. The glass float was developed through cooperation with one of the owners of the Hadeland Glassverk in Norway, Chr. Berg.

The earliest mention of these "modern" glass fishing floats is in the production registry for Hadelands Glassverk in 1842. The registry shows that this was a new type of production.

The earliest evidence of glass floats being used by fishermen comes from Norway in 1844 where glass floats were on gill nets in the great cod fisheries in Lofoten. By the 1940s, glass had replaced wood or cork throughout much of Europe, Russia, North America, and Japan. Japan started using the glass floats as early as 1910. Today, most of the remaining glass floats originated in Japan because it had a large deep sea fishing industry which made extensive use of the floats; some made by Taiwan, Korea and China. In Japanese, the floats are variably known as ukidama (浮き玉, buoy balls) or bindama (ビン玉, glass balls).

Glass floats have since been replaced by aluminum, plastic, or Styrofoam.

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