What is borosilicate glass?

Borosilicate glass, or boro, is a unique and special kind of glass created by adding boron and other metals to the traditional glassmaker's ‘frit’ of silicate sand, soda and ground lime. Boro glass is world-renowned for its superior durability, chemical- and heat-resistance. Borosilicate  glass melts at a higher temperature than ordinary glass, and thus requires very specialized equipment, making it far more expensive to produce.

When boro glass is placed under exceptionally high temperatures (often as high as 2,400°F) and combined with other mixtures of boro glass, the metallic compounds interact to produce amazingly rich colors and visual effects that cannot be reproduced in other types of glass.

At Fire and Ice Foundry, we work with borosilicate glass exclusively in our beads. While this glass is more expensive and time-consuming to work with, the end result is a far superior piece, approximately 2.3 times stronger than normal glass (we often bounce our beads on a cement floor to demonstrate their durability). Combined with the highly  unique colors and visual effects, boro glass is easily the strongest, most challenging and visually appealing glass medium an artist can work with.

Compare this with the imported (usually Chinese) glass one is likely to encounter on most garden-variety jewelry (which is often machine-made by the millions). A shrewd buyer will find that the imported beads are all identical and very easy to break, chip or otherwise damage, due to the use of inferior and softer glass.

All of our beads are hand made, one-at-a-time, in our studio here in Ohio. Even if we were to reuse the same ‘recipe,’ the end result would not be exactly the same ever again, due to the variances in the mixtures of the boro compounds. This means that each piece is one-of-a-kind and completely unique. Our beads are available by themselves, or set into completed beadwork jewelry, as unique, beautiful and handmade as its focal bead. Be assured that when you purchase from Fire and Ice Foundry, you get a truly handmade, original, and all American made piece of wearable art.


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