Below is a brief history about glass fishing floats.
The use of the first glass fishing floats can be traced as far back as 1840. The Norwegians used a small egg-sized float on which they tied a fishing line and a hook. As the use of nets increased, Norway went on to produce other sizes of floats since glass was an economical method of supporting the nets and offered plenty of buoyancy. Many European countries soon began using glass floats. Trademarks or embossing began appearing on the floats to identify the users and manufacturers of the floats.

Around 1910, far eastern countries, primarily Japan began manufacturing and using glass floats, hence their most popular name - Japanese Glass Fishing Floats. To accommodate different fishing styles and nets, the Japanese experimented with many different shapes of floats, from as small as 2 inches in diameter to the gigantic size of 20 inches in diameter.  Most floats are shades of green because the glass used was primarily recycled sake (wine) bottles, but clear, amber, aquamarine, amethyst, blue and other colors were also produced. The most prized and rare color being a red, or cranberry hue. These were expensive to make because gold was used to produce the color. Other brilliant jewel tones such as emerald green, cobalt blue, purple, yellow and orange were primarily made in the 1920´s-30´s. The majority of the colored floats you will find for sale today are replicas.

Cork and aluminum floats appeared around 1920. These soon began to replace glass floats since they were more durable and could provide holes or eye features that made net attachment easier and more reliable. As manufacturing techniques improved, plastic floats soon followed.  Unfortunately for net fisherman, glass floats would often escape their nets. Today, millions of glass floats are probably still floating in the world's oceans.  When tide and weather conditions are just right, you can find glass floats that wash up on the beaches of Washington, Oregon and Alaska. Sometimes, several may arrive together in the same location. Often, these floats roll safely onto shore or may be tangled in seaweed or other flotsam. Sadly, they also can be shattered if the float should land on a rocky coastline. During stormy periods they can be thrust hundreds of feet onshore and will remain there until some lucky hunter should find it.