The raw materials for making purple mud, commonly known as azure mud, reddish brown mud, bottom-cleaning tank mud and red mud, are the main raw materials for making purple mud pots (vessels).

Zisha pot is the most common, which is characterized by not grabbing the fragrance of tea and not cooking soup. The wall of the pot absorbs the fragrance of tea, and the empty pot keeps boiling water for a long time.

The origin of purple clay belongs to inland lake and coastal lake facies sedimentary deposits, which are formed by external deposition and buried deep in the mountainside. Both purple mud and green mud are produced from a mud mine. Nail mud is a kind of ridged clay, purple-red, shaped like armor, hence the name "nail mud".

The reserves of A-mud in A-mud mine are the most, while the reserves of purple mud and green mud are less, and purple mud only accounts for 3-4% of the total reserves. Purple mud is the interlayer in nail mud, and green mud is the interlayer in purple mud interlayer, so it is called "mud in mud, rock in rock"

Extended data

Yixing teapot is the most famous. Yixing teapot tea has no real fragrance of tea and soup, and can keep the color, fragrance and taste of tea for a long time. Purple sand tea set is also favored by people because of its simple and unique shape and excellent temperament. After being soaked in tea and rubbed by hand, it will turn into ancient jade color.

Purple mud is indeed a unique raw material in Yixing, which has all the chemical and mineral components necessary for pottery making. Microscopic observation shows that the main minerals of purple mud are Yingshi, clay, mica and hematite. Reasonable chemical, mineral and particle composition makes purple mud have good technological properties such as good plasticity, high green strength and dry shrinkage. The fineness of purple mud grinding should be screened by 60 mesh sieve.

Refer to Baidu Encyclopedia-Purple Sand Mud

Reference materials? Baidu encyclopedia-teapot