Why borosilicate kettles belong in a tea kitchen
Borosilicate glass arrived in the early 20th century as a laboratory curiosity — heat-tolerant, chemically inert, and shock-resistant enough to go from burner to cold counter without cracking. Tea people soon recognised what scientists already knew: transparency is control. When you can’t see the water, you miss the conversation between heat and leaf. A glass kettle turns that conversation into a visible arc. The Chinese tea tradition names these stages — shrimp eyes (70–80 °C), crab eyes (80–85 °C), fish eyes (85–90 °C), and the string of pearls of a rolling boil (95–100 °C). Each unlocks a different tea: crab eyes for green teas, fish eyes for oolongs, full rolling for pu-erh. Beyond temperature, glass refuses to leave a fingerprint on the water’s chemistry. Stainless steel can nudge the pH; glass sits neutral. That matters when you’re building water from scratch or tuning a delicate silver needle. Visit thetea.app’s encyclopedia entry on water for tea for the full chemistry story, or join our course Water as the Sixth Taste on tea.school to learn how dissolved gases and minerals shape every infusion. The Liuzhou workshop that makes our kettles works borosilicate by hand, shaping globes that sit steady on gas, induction (with a diffuser), and electric coil. Lightweight but strong, these kettles move from stove to gongfu tray with the quiet confidence of a tool that’s been doing one thing well for decades.
From the Liuzhou workshop — three sizes for every flame
Each stovetop borosilicate kettle is hand-formed by Gao Liuzhou, a glassblower whose workshop sits in the limestone hills of Guangxi. Simple, honest, and quietly beautiful.