The seals that a Chinese scholar would use are a refined art form with a functional purpose. Traditionally in China, a seal using vermillion ink paste is the required accompaniment to a signature. The seal validates the signature’s authenticity and thus is highly prized and closely guarded. Chinese Officials since the Song Dynasty (960 A.D.) have had a seal of office. This seal would be held closely; if lost, the official would be dismissed from office. Scholars had not only a signature seal and an official seal (if so employed), but would also have had leisure seals with commonly admired sentiments, such as "Gracing the kingdom" or "The sun among the clouds".
Different scripts are used as seal scripts. They are often illegible to common readers but are based on ancient forms of script. There are two basic forms of script: Zhuan and Li. The basic Zhuan scripts are the small seal script (Qin Dynasty) or the Han seal script (Han Dynasty). The Li script was the official written or clerical script of the Han Dynasty. In addition to these scripts there are archaic scripts (Pre-Qin) and a variety of other decorative scripts including pictorial seals. In collecting seals, one can examine the exactitude of the calligraphic rendering in this form with well-planned and proportionate distribution of the characters.
The range of materials that seals are carved from varies as much as other well-collected Chinese arts, such as Snuff Bottles and Archers’ thumb rings. Seals can be made from soft materials that are relatively easy to carve, such as wood, ivory, soapstone and horn. Harder materials such as bronze, jade, agate, glass and crystal proved more difficult to achieve the fine line qualities of the script that softer materials offered.
The forms of seals can range from a simple block to an intricate sculpture. The most widely used form for an official’s seal is that of a lion on top of a plinth, symbolizing valor, power and energy. In other types of seals the lion is rendered as both different zoomorphic forms and religious-based icons. With these variations of theme, form, type, material and script, different collecting foci can be used as parameters of collecting within this broad category.