History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c18.s4.t2.8

v1.c18.s4.t2.8

Besides metals, a few minerals and their groups are also found mentioned in this text, viz.*Abhraka* (Mica), *Vaikrānta* (Turmaline), *Vajra* (Diamond) and *Kānta* (Magnetite) are included in *Śakti* group that means these are used to induce *Śakti* (high potentiation) in Mercury and are described in detail.