Minerals and Metals in Ancient India v2.c41.s5.3

v2.c41.s5.3

Conch-shells (2.6.4; 7.12.24) and oyster-shells (2.11.35) were used not only for making bangles and other decorative items, but also to prepare *kṣāra* or alkali by calcination of calcium carbonate contained in it to alkaline calcium hydroxide (2.12.27). The word *kṣāra* meant ‘an extract’ and denoted sugar (2.15.14) as well as alkali from calcareous materials (2.12.27) and from the ash of barley *yavakṣāra* (2.12.9; 2.15.15) or *māṣa*-bean, sesamum, *palāśa*, etc. (2.12.9).