History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c20.s1.4

v1.c20.s1.4

Tuvarī or alum is described as a fragrant earth produced in the mountains of Surat in Saurastra and which dyes cloth and fixes the colour of maddar. It is called saurāṣṭrī also and when applied to white cloth it serves as a mordant for dyes. A variety of it is slightly yellow and is called pītikā and another variety sphuṭikā is soft and acidic⁶. The two varieties of tuvari are also called phullikā and khaṭikā⁷. In Amarakośa of 600 A.D., kāṅkṣī, tuvarī and saurāṣṭraja are mentioned as synonyms. Since a large number of dye-stuffs and dyed textiles are mentioned in ancient texts, it becomes evident that dyers were using basic mordants like iron sulphate and aluminium sulphates for acid dyes and that for basic dyes, acid mordants like tannic acid were used.