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Rasaratna-samuccaya has named eight maharasas: abhraka or mica, vaikranta, maksika (pyrites), vimala (iron pyrite), adrija (bitumen), sasyaka (blue vitriol), Capala (bismuth or lead or tin ores yielding quick- -melting metals) and rasaka (zinc ore). These were recommended for 'collection after identification' (2.1). Abhraka, tentatively translated as mica, was defined as class of material which binds mercury, and therefore these materials were probably sulphur-bearing mica-like substances. Abhrakas were classified in Rasaratna-samuccaya under four categories depending upon their colours and behaviours when put on fire.

Ix-6 Pinaka variety of abhraka was described as white and 'setting free its dalas or folds' when put on fire: pinakam pavakottaptam vimumcati daloccayam (Rasaratna-samuccaya 2.5) This material could be vermiculite which indeed swells (due to expansion of water-rich lattice and elimination of water molecules) when put on fire. Naga variety of abhraka is red and 'produces hissing sound like that of snake when put on fire' naga nagavat pavakam samsthitam (Rasaratna-samuccaya 2.6) The material could be red lead or, if the colour is not red, even mica-resembling galena; these produce, on reduction, lead or the metal known as naga or ahi. Manduka variety is yellow, bursting into fragments when put on fire Vajra variety of abhraka is It was black and does not change when put on fire (2.7-2.8). believed that yellow mica could produce gold, and white mica could produce silver through reaction with mercury (Rasaratna-samuccaya 2.9-2.10). This belief led to elaboration of the procedures for satvapatana (metal-extraction) from abhraka (2.27-2.38) We have already mentioned vaikranta which was known both. as a gem as well as one of the maharasas. Maksika was known to occur in two varieties: - majhiko dvividho hemamasika staramaksika (Rasaratna-samuccaya 2.81)

IX-7 Hemamaksika or gold-coloured maksika, occurring around Kanyakubja, Tapti river etc., was most probably copper pyrite or chalcopyrite which could be reduced by organic materials such as sneha gavyajva (cow's ghee or butter-fat) to produce the red metal, copper (2.85-2.89). Tara maksika looked silvery and was probably iron pyrite. Vimala also represented pyrite o group minerals and sulphides. There were hema and tara varieties as in maksika, and these were probably the same as chalcopyrite and pyrite. A third variety Kamsya vimala has been identified as arsenopyrite. Another particular variety, most probably galena, was described (2.96-2.102) as 'cubic in shape, having angles and facets, brilliant, reducible by borax and charcoal to yield sisaka-type metal': vartulah konasamyuktah sat 鈥�prastha ko kile dharmato vimala ..... vimala !.... sisasannibhah silajatu or bitumen was known to be an exudate from the lower part of the Himalayas. It could be sasastva (with metallic content) or nihsatva (without any metallic content) (2.109) a peacock Sasvaka or blue vitriol was likened to the blue neck of (2.125). Rajanighantu commented that sasyaka is a natural material, while tuttha or tutthaka (copper sulphate) is artificially prepared. "In the absence of one, the other may be used". The chemical identity of the two was not firmly established. Similarly, while describing satvapatana or metal extraction from sasyaka by reduction-heating in a crucible, the identity of the red metal 'looking like indragopa or coccinella insect with copper was guessed but not confidently affirmed. (Rasaratna-samuccaya 2.133-2.134) : indragopakrti indragopakrti caiva satvam tamrarupam satvam mumcati samsyakam ||

IX-8 Capala was defined as a material which melts quickly like vanga or tin when put on fire vagavad dravate va capalarasena kirtitah vahnau (Rasaratna-samuccaya 2.143) and has six edges, brilliance and heaviness. Capala could be yellow, white, red or black. Was the heavy black variety galena, yielding low-melting metal lead? As a matter of fact, Rasaratna-samuccaya does. refer to nagasambhuta capala, or lead-bearing capala (8.41-8.42) and vangasambhuta capala, another variety containing tin (8.43-44). Some scholars have claimed that a third variety of capala contained bismuth. Details about rasaka or zinc blende would be mentioned later in connection with zinc metallurgy.