Some purple clay Teapots develop tea stains and black spots over time. Why does this happen? Are black spots and tea stains the same thing?

Black Spots

Black spots on a Purple Clay Teapot refer to sesame seed or rice grain-sized black dots that appear on the surface of the pot during normal use.

Black Spots

Black spots can also be considered a type of tea stain, mainly due to the pot not being fully vitrified (commonly known as underfiring), which results in a high porosity rate. The pot allows both air and water to pass through, causing the tea inside to seep out and form streak-like tea stains when the pot dries.

Many enthusiasts believe that only duanni clay (a type of purple clay) exhibits black spots, but this is not the case.

Black Spots

All types of clay are prone to black spots if they have not reached the vitrification temperature. Duanni clay shows these spots more prominently because of its light color, while darker clays may go unnoticed.

Black spots can be found all over the surface of the purple clay teapot; sometimes in streaks; other times concentrated in certain areas, such as around the lid or bottom rim.

Tea Stains

If a used purple clay teapot is merely rinsed without thorough cleaning, over time, a thick layer of tea stains will accumulate on the walls.

Tea stains form when organic substances in tea are exposed to air and undergo oxidation and polymerization, as well as from the oxidation of tannins with metal elements.

Thick Tea Accumulation

In the past, many aficionados of Gongfu tea had teapots covered in tea rust and a thick layer of tea stains, which they referred to poetically as a “tea mountain.”

Modern science tells us that tea stains contain various harmful metals such as cadmium, lead, arsenic, mercury, and nitrosamines, as well as carcinogenic compounds.

Tea Stains

If not cleaned promptly, these toxic substances can easily enter the drinker's digestive system along with the tea water. Therefore, it is important to clean tea stains regularly.

It is important to note that reliable methods should be used to remove tea stains from purple clay teapots, as many online suggestions do not apply.

For example, toothpaste and vinegar, commonly used to remove tea stains from ceramics, glass, and plastic, which do not absorb odors, are not suitable for purple clay teapots.

Purple clay teapots should be cleaned using baking soda or salt mixed with water. When wiping, use a clean cloth or sponge free of oil stains.

The best and most hygienic practice is to rinse the Teaware with hot water immediately after Drinking Tea and wipe it clean. This is the most effortless and hygienic way to enjoy tea.