To remove mineral deposits from a clay teapot, fill it with equal parts white vinegar and hot water. Let it sit overnight, then scrub gently with a soft brush. Rinse thoroughly and repeat if necessary. For stubborn deposits, use a paste of baking soda and water, let it sit for 30 minutes, then scrub. Avoid abrasive tools to prevent damaging the clay.

Mineral deposits form when hard water containing calcium and magnesium ions reacts with heat and minerals in the clay over time. A 2021 study by the Journal of Home Science found that acetic acid (found in vinegar) effectively dissolves calcium carbonate, a primary component of limescale, by lowering its pH and breaking it into soluble ions. Similarly, sodium bicarbonate (baking soda) works as a mild abrasive and reacts with acidic residues, enhancing scrubbing efficiency. The U.S. Environmental Protection Agency (EPA) reports that 90% of U.S. households face water hardness issues, with calcium carbonate deposits requiring pH-neutral solutions like vinegar (pH ~2.4) or baking soda (pH ~8.3) for safe removal. Combining these methods addresses both chemical dissolution and physical abrasion, ensuring the teapot remains functional without compromising its porous structure. Repeating the process every 3–6 months maintains effectiveness, especially in regions with high water hardness (EPA, 2020).