Duan ni is a type of purple clay. A Teapot made from duan ni is called a duan ni purple clay teapot. Duan ni can be basically divided into three types: original mine duan ni, old duan ni, and blended duan ni. Old duan ni is original mine duan ni that has undergone a certain period of aging. Golden duan and sesame duan are blended duan nis, such as sesame duan which is made by blending purple clay particles into Ben Shan green clay. Blended clay is primarily used to highlight the texture of the clay, and in recent years, many enthusiasts have come to appreciate it. The key lies in how well the blending is executed, and whether one likes it or not depends on personal aesthetic preferences.
Duan ni purple clay Teapots have some distinctive characteristics compared to other types of teapots. A characteristic of high-quality duan ni purple clay teapots is that the purple clay particles are not very noticeable. In Ben Shan green clay, they seem to only serve the purpose of altering its color. There are layers, like jade. Duan ni cannot be fired to achieve the pure Ben Shan green color; when fired, Ben Shan green clay produces a delicate, pure yellow hue. Duan ni is used in the production of ceramic jars. When duan ni is used to make purple clay ware, there will be variations, not only in color but also in effects such as blended sand. Knowing the characteristics of duan ni purple clay teapots makes it easier to identify whether a teapot is made of duan ni.
I. Look at the color:
The color of genuine purple clay, whether purple, yellow, red, or any color in between, should have the allure of jade, with a luster that is matte, as if coated with oil, becoming glossier with more polishing. No wax should be applied, and no polishing should be done. One can refer to the material effect of aged jade. The rarer the material, the more valuable it is, due to limited resources.
II. Listen to the sound:
A purple clay teapot is a superior type of pottery, so the sound it produces should be that of pottery. After steeping Tea, the sound should be muffled, dull, and deep, not metallic or as crisp as Porcelain. A muffled sound indicates good breathability of the material, which helps retain the aroma of tea and prevents it from going stale.
III. Feel the texture:
A purple clay teapot should have a smooth, comfortable feel, with particles that are rounded despite their presence. Generally, a particle size of 32 to 60 mesh is suitable. The texture of sand powder processed traditionally by hand, using stone grinding, differs from that produced by machine.
IV. Effect of nurturing the teapot:
With a good purple clay teapot, after a little bit of tea brewing and wiping dry with a cloth, one can see a lustrous matte color quality, with a heavy oily appearance. The longer the teapot is nurtured, the deeper and more rustic the color becomes, eventually imbuing the teapot with a spiritual quality, allowing it to connect with human emotions.