Glass can be made from an array of combinations depending on the application for which it is intended. Choosing the right formulation is critical to ensure the end product will withstand the conditions it's subjected to. Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (~3 × 10−6 K−1 at 20 °C), making them resistant to thermal shock, more so than any other common glass. Such glass is less subject to thermal stress. Pyrex™ began making kitchenware from Borosilicate glass in 1915. While they became the most common brand name for the glass, the US based product line has moved to a less expensive “soda-ash”.


    Borosilicate is used extensively in the glassblowing process of lamp-working; whereby the glassworker uses a burner torch to melt and form glass, using a variety of metal and graphite tools to shape it. Borosilicate is referred to as "hard glass" and has a higher melting point (approximately 3,000 °F / 1648 °C) than "soft glass", which is preferred for glassblowing by bead makers. Raw glass used in lamp-working comes in glass rods for solid work and glass tubes for hollow work, like tubes and containers, and now beverage straws.

What All The Science Means to Our Customers


    It wasn’t hard to decide on Borosilicate as our medium of choice whether we are making decorative ornaments or glass drinking straws. The strength it affords is unmatched by any other glass. Withstanding high temperatures allows artisans the ability to use torches and ovens to manipulate glass rods and tubes into masterpieces. At Elizur International, all our products are made from premium Borosilicate glass to ensure top quality and the best value for our customers. 

Find out more

read the full Borosilicate Glass Whitepaper

Our guide to the science behind Borosilicate glass and why we use it in our products.

Borosilicate Glass Whitepaper (pdf)