Minerals and Metals in Ancient India v2.c41.s6: Metallic Ores

Minerals and Metals in Ancient India v2.c41.s6

Language: English

Metallic Ores

v2.c41.s6.1

The *Arthaśāstra* is the earliest Indian text dealing with the mineralogical characteristics of metallic ores and other mineral-aggregate rocks. It recognised ores in the earth, in rocks, or in liquid form, with excessive colour, heaviness and often strong smell and taste (2.12.1).

v2.c41.s6.2

The text described a ‘liquid ore’ which seems to be a petroleum like bio-geogenetic material. This liquid ‘flows inside a hole, a cave, a table-land, dug-out mountain whose regions are known to contain gold ore’. This liquid is coloured yellow, viscous, clear and heavy and thrown in water, spreads on the surface like oil’ (2.12.2-3). The description agrees to that of petroleum of asphalt basis as found in the Punjab and Baluchistan. (Roy, 1946:113) A very similar material with stronger small and taste was known to be bitumen or śilājatu (2.12.4). These materials were erroneously believed to contain gold and mentioned as ‘metallic ores’ or dhātu.

v2.c41.s6.3

The Arthaśāstra described a gold-bearing ore which Roy (1946: 113-14) has interpreted as typical auriferous pyrite. We reproduce the translation of the relevant section (2.12.5) of the Arthaśāstra with Roy’s interpretation in the parentheses:

v2.c41.s6.4

Those ores which are obtained from the planes, or slopes of mountains; which are either yellow (pyrite is yellow), or red as copper, or reddish yellow (pyrite often becomes pseudomorphous after limonite and then develops brown colour) which are disjoined (individual crystals of pyrite), and marked with blue lines (grain boundary of chalcopyrite and pyrite) . . . . which are marked with spots like drops of curd (quartz is the curd-white mineral), dazzlingly bright yellow as turmeric (native gold), when broken, show lines, spots or svastikas of fine sand (minute crystals of pyrite occur between larger crystals; when isolated, such layers readily crumble away and become like sand grains; separation of metallic gold in the form of rings has been reported — the svastika represents the skeleton of a gold crystal separated out of gradually decomposing auriferous pyrite); which contain globular masses (decomposed pyrite showing iron hat); and when roasted, do not split but emit foam and smoke (i.e., sulphur dioxide gas).

v2.c41.s6.5

Similarly, the silver ore described in the Arthaśāstra (2.12.6) seems to be a complex sulphide ore containing silver: “colour of a conch-shell, camphor, vimalaka (pyrite?) sasyaka (copper sulphate, an oxidation product of associated copper sulphide), containing lead (galena), añjana or antimony (as sulphide), smells like raw meat (smell of sulphur), ores which are disjoined (cube-shaped particles of cleaved galena), grey or blackish white (colours of galena, argentite or tetrahedrite); when roasted do not split, but emit much foam and smoke (galena and argentite evolve SO₂ gas, and galena forms white incrustation of lead oxide or charcoal)”.

v2.c41.s6.6

The Arthaśāstra described the sources and the qualities of good grade gold and silver ores (2.13.3-5 & 10-12). The quality had to be tested through streak on suitable stone-plate (2.13.17-27).

v2.c41.s6.7

Copper ores were stated (2.12.12) to be ‘heavy, greasy, tawny (chalcopyrite left exposed to air, tarnishes), green (colour of malachite), dark blue with yellowish tint (azurite), pale red or red (native copper)’. Lead ores were stated to be (2.12.13) grayish black, like *kākamecaka* (this is the colour of galena), yellow like pigeon bile (lead ore gossan), marked with white lines (quartz or calcite gangue minerals) and smelling like raw flesh (odour of sulphur). Tin ores could be (2.12.14) grey like saline earth (witherite?) or brown like burnt earth (cassiterite). Iron ore was known (2.12.15) to be greasy stone, pale red colour (orange limonite) or of the colour of the *sinduvāra* flower (hematite). Lahiri (1968, 1971) commented that ‘the rock with greasy feel seems to be phyllite, and that with the pale red colour, jasper’. This matches with the characteristic of the bedded iron ores of Bihar and Orissa.

v2.c41.s6.8

After describing the above metallic ores or *dhātus* of specific metals, the *Arthaśāstra* writes:

v2.c41.s6.9

काकान्ड भुजपत्रवर्णो वा वैकृन्तकधातुः
*kākāṇḍa bhujapatravaṛṇo vā vaikṛntakadhātuḥ*
(2.12.16)
That which is of the colour of *kākāṇḍa* (crow’s egg) or birch-leaf is *vaikṛntaka* ore.

v2.c41.s6.10

This presumably refers to the ore of *vaikṛntaka* (mentioned as a metal in 2.12.23; 2.17.14 and 4.1.35), the identity of which is not known. Roy (1946:113) suggested that since magnetite is black and becomes brown on surface oxidation being changed to hematite, *vaikṛntaka* ore is magnetite. In that case *vaikṛntaka* metal must be iron itself which used to be produced by the South Indians starting from the magnetite ore. It was later known as *kāntaloha*.

v2.c41.s6.11

Kangle (1986: Part II, p. 108 footnote) however quotes a view that *vaikṛntaka* could be an alloy or metal made in China. This could be nickel metal or nickel alloy. It may be recalled that during the third to first century BC, the Chinese copper-nickel alloy was used in Taxilā and north-west India for coinage, jewellery and fancy goods. This was known as *pai-t’ung* or *tutenag(ue)* or white copper. It is not certain whether *vaikṛntaka* metal was nickel or magnetite-based iron.

Linked texts (1)

Kauṭilīya Arthaśāstra — Kauṭilya, Sanskrit