The discovery of borosilicate glass
In the late 1800s, German glassmakers were trying to solve a persistent problem: ordinary glass cracked when exposed to heat or sudden changes in temperature. Traditional glass is made primarily from silica, derived from sand. While silica produces clear, workable glass, it expands and contracts significantly with heat, making it prone to breaking under the kind of conditions that cooking and scientific work demanded.
The breakthrough came when glassmakers began adding boron, a naturally occurring mineral, to molten silica. Boron changes how the glass behaves: it reduces thermal expansion, increases structural strength, and allows the glass to withstand extreme temperature changes without fracturing. The resulting material became known as borosilicate glass, and its stability quickly made it essential in laboratory equipment, scientific instruments, and cookware — anywhere heat, precision, and clarity were all required at once.
At T2, borosilicate glass brought that same thinking to teaware. Tea is brewed hot, sometimes chilled, occasionally reheated. The material holding it needs to handle that range without compromise.
Borosilicate glass vs standard glass
Most drinkware is made from soda-lime glass, the most common type of glass used in everyday tumblers and mass-market vessels. Soda-lime glass is cheaper to produce, but it's heavier, more brittle, and sensitive to temperature change. Moving it quickly from hot to cold introduces a real risk of cracking.
Borosilicate is a different material entirely. Lighter and stronger than soda-lime, it resists thermal shock, maintains clarity over time, and doesn't absorb the flavours or aromas of previous brews.
Handblown glass
Some pieces in T2's glass range are handblown, shaped by artisans using traditional techniques rather than machines. Molten glass is gathered on the end of a hollow pipe and guided slowly into its final form using breath, rotation, and simple hand tools. The process is deliberate and unhurried, and because each piece is shaped individually, no two come out exactly alike. Subtle variations in thickness, form, or the occasional small air bubble are not flaws. They're the signatures of the hand that made them.
Handblown borosilicate glass brings the best of both together: the lightness and refinement of handcraft, with the thermal strength and clarity that borosilicate provides. It's why many T2 glass teapots feel remarkably light in the hand while confidently handling freshly boiled water.
How to care for glass teaware
Most T2 glass teaware is dishwasher-safe, though handwashing in warm water will preserve clarity over time. Avoid abrasive scrubbers that can dull the surface. For double-walled pieces, check individual product pages for care guidance, as the internal air layer requires specific handling to maintain its integrity.
FAQ
What is borosilicate glass?
Borosilicate glass is made by adding boron to molten silica. The boron reduces how much the glass expands and contracts with temperature changes, making it significantly stronger and more heat-resistant than standard glass. Originally developed for scientific and laboratory use, it's now the standard for high-quality teaware, cookware, and anywhere heat, strength, and clarity are all required.
What is the difference between borosilicate and regular glass?
Standard soda-lime glass is heavier, more brittle, and prone to cracking when exposed to sudden temperature changes. Borosilicate glass is lighter, stronger, and highly resistant to thermal shock — it can handle boiling water and cold temperatures without cracking or clouding. It also maintains its clarity over time and doesn't absorb flavour or aroma from previous use.
Why does T2 use borosilicate glass?
Tea is brewed hot, sometimes chilled, and occasionally reheated. That range of use requires glass that can handle temperature changes without cracking or affecting taste. Borosilicate keeps tea tasting exactly as it should while maintaining long-term clarity and strength. It costs more to produce than standard glass, but for a material that holds tea every day, that quality decision matters.
Can T2 glass teaware handle boiling water?
Yes. Borosilicate glass is specifically designed to handle high temperatures and sudden temperature changes. T2 glass teapots, mugs, and cups can take freshly boiled water without cracking or clouding — which is exactly why T2 uses it across all glass teaware.
What is handblown glass?
Handblown glass is shaped by artisans using traditional glassblowing techniques rather than machines. Molten glass is gathered on a hollow pipe and shaped using breath, movement, and hand tools. Because each piece is made individually, subtle variations in form or small air bubbles are a natural part of the result — markers of craft, not defects. Many T2 glass teapots are handblown from borosilicate glass.
Is T2 glass teaware dishwasher safe?
Most T2 glass teaware is dishwasher-safe. Handwashing is recommended for handblown pieces and any items with printed or decorative detailing. Check individual product pages for specific guidance, particularly for double-walled pieces.
