Calligraphy with white characters on a black background should use black rice paper or calligraphy paper, white ink or white silver powder. White silver powder should be mixed with water and have moderate consistency.
The seal is a Chinese character, and the pinyin is ynzzhāng, also called stamp. It is used as stationery printed on documents to indicate identity or signature. Generally, seals are printed with pigment first, and then without pigment. When printed on a plane, there will be bumps, which is called steel seal, and some are wax prints and envelopes printed on wax or wax. Made of metal, wood, stone, jade, etc.