Boro Glass Beads

Lampwork glass beads, at Alaska Boro, are each individually made by hand. Each bead is crafted using a lampwork GTT torch heating glass in excess of 1500 degrees Fahrenheit. Lampwork beads are made using colored boro (borosilicate) glass, clear boro and 104 soft glass for alternative designs.

Borosilicate (boro) glass is best known for its very low coefficients of thermal expansion. i.e. Pyrex cooking ware. Boro is also known as hard glass which has a coefficient of expansion (COE) of 33. Soft glass, also used for making beads, has a COE of 104 to 90. Glass objects made with different glass COE’s will result in a product that is subject to cracking due to uneven thermal expansion even after annealing. Thus a glass of a COE 33 is NEVER mixed with a 104 glass!

Beads made at Alaska Boro have bead holes of five different sizes. Holes are either 1/16 inch (1.58 mm), 3/32 inch (2.38 mm), 1/8 inch (3.18 mm), 3/16 inch (4.76 mm) and 1/4 inch (6.35 mm). Hole sizes are always slightly larger than the stated size due to the thickness of the mandrel (bead) release.

Often handmade boro beads are lined with sterling sliver to have the general look of the popular Pandora style. For these ‘special’ beads, a 3/16 inch mandrel is used along with mandrel release to achieve the desired hole size.

Boro beads at Alaska Boro are kiln annealed at 1050 degrees. Beads are slowly cooled through the boro glass strain point at 950 degrees Fahrenheit using a digital PID controller to remove any stress. In addition, each bead hole is hand cleaned of release prior to or after the annealing process. Soft glass beads require a lower temperature for proper annealing.

Bead colors are dependent on viewing conditions and monitor settings. Beads will look livelier outside and somewhat muted inside. Images are as true to life in color as possible. i.e. beads that look dark on the site will look dark when received.

The size of a bead image can not be used to determine actual size. Images are larger than life to enhance the view of boro colors and designs. Please use the size data as stated in the product description to determine actual bead size. Sizes are stated in millimeters with the first dimension being the bead diameter, followed by thickness and then the approximate hole size.