This paper makes a brief description and analogy of Shoushan Tianhuang Stone and its similar seal stone, and discusses some problems concerning the difference between Shoushan Tianhuang Stone and Changhua Tianhuang Stone as well as between Shoushan Tianhuang Stone and the sliderock stone and cave stone of the same parent rock. The authors hold that, no matter where the producing area is and what the shape looks like, unified classification, naming and grading of the seal stone can be made in accordance with the major minerals so long as the seal stone is of high quality.