The present paper discusses the classification of Indus-type seals in light of their carving techniques using SEM and 3D （PEAKIT） analyses. Although data for the analyses is still limited, this study leads to an important conclusion that has not been pointed out so far, that Indus-type seals can be classified based on the shape of a cross section of the seal passing through the body of the animal depicted on the surface of the seal, namely whether the edge of the cross section is curved or angular (in some seals it is partly curved and partly angular). The two cross-section types are a result of different manufacturing techniques and carving tools and correspond to the size of the seals.
Themore, because the different shapes of the cross sections correspond to the difference of design and distribution pattern of the seals, Indus-type seals can be divided into two types. The Type-A seal is characterized by a left-facing animal motif having a curved cross section, a 'Pattern I' arrangement and a Type I boss. This type is distributed predominantly throughout the Indus Valley, excluding the Ghaggar Basin. The Type-B seal is characterized by a right-facing animal motif having an angular cross section and mainly a 'Pattern II' or 'Pattern III' arrangement and a 'Type II' boss. It is concentrated in the Ghaggar Basin. This study concludes that it is likely that both seal types show the regional variations of Indus-type seals.
The next stages in the study of the seals will be to accumulate SEM and 3D (PEAKIT) data of Indus-type seals and to undertake an experimental archaeological study in order to fully understand and reconstruct the manufacturing techniques and tools.
