Rasayana Shastra (रसायनशास्त्रम्) - Revision history

Fordharma at 11:24, 10 June 2025

2025-06-10T11:24:05Z

Fordharma: /* Atomistic Conception of Matter */

2025-06-10T08:44:58Z

Atomistic Conception of Matter

Show changes

Fordharma: /* Purification */

2025-06-06T15:03:09Z

Purification

Fordharma: /* Purification */

2025-06-06T15:02:37Z

Purification

Fordharma: /* Chemical Arts and Crafts */

2025-06-06T14:30:10Z

Chemical Arts and Crafts

Show changes

Fordharma: /* Classification of Chemical Substances */

2025-06-04T17:03:03Z

Classification of Chemical Substances

Fordharma: /* Dyes, Mordants and Pigments */

2025-06-04T16:21:51Z

Dyes, Mordants and Pigments

Fordharma: /* Glass Industry */

2025-06-04T16:19:44Z

Glass Industry

Fordharma: /* Classification of Chemical Substances */

2025-06-04T16:17:38Z

Classification of Chemical Substances

Fordharma: added content

2025-06-03T10:56:07Z

added content

@@ Line 38: / Line 38: @@
 == Origin and Properties of Matter ==
-Chemistry involves the study of fundamental properties of matter and atoms, and their inter-relationships. The Ayurvedic period constitutes the most flourishing and fruitful age of ancient India relating to the accumulation and development of chemical sciences which at that time was closely associated with medicine. The physical and chemical theories were intricately associated with the [[Srshti Siddhanta (सृष्टिसिद्धान्तः)|srshti siddhantas]] propounded in the vedic, upanishadic and darshana shastras. Ayurveda was founded on the theories of cosmic evolution in [[Ayurveda and Darshanas (आयुर्वेदः दर्शनानि च)|Darshanas]] most importantly of Samkhya and Vaiseshika.<ref name=":1" />
+Chemistry dealt primarily with the composition and changes of matter and the underlying principles were deduced in a systematic and logical way purely based on thoughts with little or no experimental proofs. Yet many such theories, the products of intellectual perfection and sublime intuition, stand in good comparison with some of the most recent and advanced scientific ideas of the present time. Chemistry involves the study of fundamental properties of matter and atoms, and their inter-relationships. The Ayurvedic period constitutes the most flourishing and fruitful age of ancient India relating to the accumulation and development of chemical sciences which at that time was closely associated with medicine. The physical and chemical theories were intricately associated with the [[Srshti Siddhanta (सृष्टिसिद्धान्तः)|srshti siddhantas]] propounded in the vedic, upanishadic and darshana shastras. Ayurveda was founded on the theories of cosmic evolution in [[Ayurveda and Darshanas (आयुर्वेदः दर्शनानि च)|Darshanas]] most importantly of Samkhya and Vaiseshika.<ref name=":1" />
 === Cosmogenesis ===
-Chemistry dealt primarily with the composition and changes of matter and the underlying principles were deduced in a systematic and logical way purely based on thoughts with little or no experimental proofs. Yet many such theories, the products of intellectual perfection and sublime intuition, stand in good comparison with some of the most recent and advanced scientific ideas of the present time. Here we come across a few ancient concepts with particular reference to srshti (theories of cosmogenesis) and origin of jagat (universe) with respect to matter and particles and their connection with chemistry.
+The Vedas take the universe to be inﬁnite in size. The universe was visualized in the image of the cosmic egg, Brahmanda. Beyond our own universe lie other universes. Here we come across a few ancient concepts with particular reference to srshti (theories of cosmogenesis) and origin of jagat (universe) with respect to matter and particles and their connection with chemistry.
 * Rig veda (10.121.1) mentions Hiranyagarbha reflecting the concept of cosmic egg and origin of universe from an egg.
 * Satapatha Brahmana (6.1.3.1-5) propounded a theory of material evolution.<ref name=":2" />

@@ Line 203: / Line 203: @@
 * '''Bidri Alloy''': The alloy produced in the South Indian town of Bidar, contained Zinc (76-98%), Copper (2-10%), at times Lead (1-8%), tin (1-5%) and trace of Iron. Darkening of the Bidriware made was done by applying a paste of ammonium chloride, potassium nitrate, sodium chloride and copper sulphate. Several impressive vessels, ewers, pitchers, vessels and huqqa bases were made of bidri ware with patterns influenced by the fine geometric and floral patterns and inlayed with gold and silver metals.
-== Purification ==
+== Purification Processes in Ayurveda ==
 The detoxification or purification process of any toxic material used for medicinal purposes is termed as “''Śodhana''”. The process is specially designed for the drugs from mineral origin; however, it is recommended for all kinds of drugs to remove their ''doṣās'' (impurities or toxic content).  The concept of ''Śodhana'' in Ayurveda not only covers the process of purification/detoxifcation of physical as well as chemical impurities but also covers the minimization of side effects and improving the potency/therapeutic efficacy of the purified drugs.<ref>Maurya, S. K., Seth, A., Laloo, D., Singh, N. K., Singh Gautam, D. N., & Singh, A. K. (2015). Śodhana: An Ayurvedic process for detoxification and modification of therapeutic activities of poisonous medicinal plants. ''Ancient Science of Life'', ''34''(4), 188. <nowiki>https://doi.org/10.4103/0257-7941.160862</nowiki></ref> The minerals or metals are invariably subjected to purification processes in Ayurvedic preparations and the processes are complicated ones. Though these processes are meant for ‘purifying’ the substances, more often than naught, some extraneous material is added onto them. In general, purification means, according to the rasasastra texts, removal of the deleterious principles present in the naturally occurring substances, so that they become fit for internal use.<ref name=":8" /> Examples include

@@ Line 204: / Line 204: @@
 == Purification ==
-The minerals or metals are invariably subjected to purification processes in Ayurvedic preparations and the processes are complicated ones. Though these processes are meant for ‘purifying’ the substances, more often than naught, some extraneous material is added onto them. In general, purification means, according to the rasasastra texts, removal of the deleterious principles present in the naturally occurring substances, so that they become fit for internal use.<ref name=":8" /> Examples include
+The detoxification or purification process of any toxic material used for medicinal purposes is termed as “''Śodhana''”. The process is specially designed for the drugs from mineral origin; however, it is recommended for all kinds of drugs to remove their ''doṣās'' (impurities or toxic content).  The concept of ''Śodhana'' in Ayurveda not only covers the process of purification/detoxifcation of physical as well as chemical impurities but also covers the minimization of side effects and improving the potency/therapeutic efficacy of the purified drugs.<ref>Maurya, S. K., Seth, A., Laloo, D., Singh, N. K., Singh Gautam, D. N., & Singh, A. K. (2015). Śodhana: An Ayurvedic process for detoxification and modification of therapeutic activities of poisonous medicinal plants. ''Ancient Science of Life'', ''34''(4), 188. <nowiki>https://doi.org/10.4103/0257-7941.160862</nowiki></ref> The minerals or metals are invariably subjected to purification processes in Ayurvedic preparations and the processes are complicated ones. Though these processes are meant for ‘purifying’ the substances, more often than naught, some extraneous material is added onto them. In general, purification means, according to the rasasastra texts, removal of the deleterious principles present in the naturally occurring substances, so that they become fit for internal use.<ref name=":8" /> Examples include
 # '''Sulphur''' is purified by melting it in the medium of cow’s ghee and straining the molten mass through a cloth into milk or the juice of Bhrhgaraja kept in a pot. It is then washed with warm water and the process is repeated several times. Purification of sulphur is considered necessary as otherwise the impure sulphur, when taken in, would produce harmful effects such as loss of beauty, strength and vision. There are many methods for purification of sulphur using various materials.
@@ Line 211: / Line 211: @@
 # Purification of '''mercury''' involves eight to eighteen methods. Mercury is purified by rubbing it for three days with the decoction of certain plants like kuman (Aloe indica), citraka (Plumbago zeylanica) and red mustard, or by rubbing it with lime and filtering through a cloth. Thereafter it is again rubbed with some quantity of garlic and common salt, and washed.
 # The '''gems''' are purified by subjecting them to the action of the ‘vapours’ of a plant called jayanti.
 == References ==
 [[Category:Shastras]]
 <references />

@@ Line 133: / Line 133: @@
 The well-known rasashastra texts like the Rasahrdaya, the Rasarnava, the Rasaratnasamuccaya and the Rasaprakasasudhakara have classified the chemical substances into<ref>Bose, D. M., Sen, S. N., & Subbarayappa, B. V. (1971). A concise history of science in India. New Delhi: Indian National Science Academy. pp. 322-326</ref>
-# '''Maharasas''': They are a group of minerals which have been recognized as most useful for the potentiation of [[Mercury or Parada (पारद)|Mercury or Parada]].<ref name=":9">Bhagwat, V. S. R., Kurkute, B. R., Shinde, B. T., & Tapare, S. K. (2017). CLASSIFICATION OF RASADRAVYAS IN RASASHASTRA. ''World Journal of Pharmaceutical Research'', ''6''(4), 792–802. <nowiki>https://doi.org/10.20959/wjpr20174-8226</nowiki></ref> They are eight in number, abhraka (mica), vaikranta (a precious stone having eight surfaces and six angles, probably tourmaline), maksika (copper pyrites), vimala (iron pyrites), silajatu (bitumen), sasyaka (copper sulphate), capala (a compound of bismuth or selinium) and rasaka.
+# '''Maharasas''': They are a group of minerals which have been recognized as most useful for the potentiation of the rasa namely [[Mercury or Parada (पारद)|Mercury or Parada]].<ref name=":9">Bhagwat, V. S. R., Kurkute, B. R., Shinde, B. T., & Tapare, S. K. (2017). CLASSIFICATION OF RASADRAVYAS IN RASASHASTRA. ''World Journal of Pharmaceutical Research'', ''6''(4), 792–802. <nowiki>https://doi.org/10.20959/wjpr20174-8226</nowiki></ref> They are eight in number, Abhraka (Mica; Double silicate of aluminium and Potassium or sodium), Vaikranta (Tourmaline; K<sub>2</sub>OAl<sub>2</sub>O<sub>3</sub>6SiO<sub>2</sub>), Makshika (Chalcopyrite/Copper pyrite; Cu<sub>2</sub>S, Fe<sub>2</sub>S<sub>3</sub>), Vimala (Iron pyrite; Fe<sub>2</sub>S<sub>3</sub>), Shilajatu (Black bitumen or mineral pitch), Sasyaka (Copper sulphate/blue vitriol; CuSO<sub>4</sub> 7H<sub>2</sub>O), Rasaka (Zinc ore; ZnO, ZnS, ZnCO<sub>3</sub>), Chapala (Bismuth/selenium).
-# '''Uparasa''': The eight uparasas are: gandhaka (sulphur), gairika (red ochre), kasisa (iron sulphate), tuvari (alum), talaka (orpiment), manah-sila (realgar), anjana (collyrium; compounds of antimony) and kankustha (probably tinstone or cassiterite).
+# '''Uparasa''': These drugs are not equivalent to Parada, but properties of this group of drugs possess less gunas than Parada and indicate usefulness in different procedures of parada or its action towards parada. The eight uparasas are:Gandhaka (Sulphur; S), Gairika (Ochre; Fe<sub>2</sub>O<sub>3</sub>), Kasisa (Ferrous sulphate/ green vitriol; FeSO<sub>4</sub>7H<sub>2</sub>O), Kankshi (Potash alum; K<sub>2</sub>SO<sub>4</sub> Al<sub>2</sub>(SO)<sub>3</sub>24H<sub>2</sub>O), Haratala (Orpiment, yellow arsenic; As<sub>2</sub>S<sub>3</sub>), Manahshila (Realgar; As<sub>2</sub>S<sub>2</sub>), Anjana (Collyrium), Kankushta (Gambose tree extract).
-# '''Dhatu''': Here usually seven metals are named: svarna (gold), rajata or tara (silver), tamra (copper), loha (iron), naga (lead), vanga (tin) and yasada (zinc). But, the three alloys (misraloha), viz. brass (pittala), bell-metal (kamsya) and a mixture of five metals (vartaka), also come under the category of dhatu. There are textual differences of which metals comprise metals. Rasarnava mentions six metals including copper but Rasaratnasamuccaya not according a place to copper among the dhatus.
+# '''Dhatu''': Dhatus are the drugs which are been extracted (removed forcely) from their ore, (by melting or process of distillation)similarly the diseases are removed forcely from the body by them so they are called as Loha.<ref name=":9" /> Here usually seven metals are named: svarna (gold), rajata or tara (silver), tamra (copper), loha (iron), naga (lead), vanga (tin) and yasada (zinc). But, the three alloys (misraloha), viz. brass (pittala), bell-metal (kamsya) and a mixture of five metals (vartaka), also come under the category of dhatu. There are textual differences of which metals comprise metals. Rasarnava mentions six metals including copper but Rasaratnasamuccaya not according a place to copper among the dhatus.
-# '''Ratna''': The ratnas generally are precious gems. The principal gems used by the rasavadins are: vaikranta (also classed under maharasa), suryakanta (sun-stone; aventurine feldspar mainly containing silicate of sodium and potassium with disseminated particles of red iron oxide which cause fire-like flashes of colour), candrakanta (moon-stone; a type of feldspar containing silicates of aluminium, sodium, potassium, calcium, barium, etc., which possesses a bluish pearly opalescence), hiraka (diamond), mauktika (pearl), garudodgara (emerald), rajavarta (lapis lazuli), marakata (topaz), nila (sapphire) and padmaraga (ruby).
+# '''Ratna''': The ratnas generally are precious gems. They are of mineral & animal origin which are found in rocks and are formed during the crust formation of the earth. They are durable, colorful & rare and the most valuable entity. These are classified on the basis of; Structure, Relation to the planets, Opacity & Transparency, Beauty and scarcity. The principal gems used by the rasavadins are: vaikranta (also classed under maharasa), suryakanta (sun-stone; aventurine feldspar mainly containing silicate of sodium and potassium with disseminated particles of red iron oxide which cause fire-like flashes of colour), candrakanta (moon-stone; a type of feldspar containing silicates of aluminium, sodium, potassium, calcium, barium, etc., which possesses a bluish pearly opalescence), hiraka (diamond), mauktika (pearl), garudodgara (emerald), rajavarta (lapis lazuli), marakata (topaz), nila (sapphire) and padmaraga (ruby).
-# '''Visha'''
+# '''Visha:''' Rasarnava appears to be the first text to mention about Visha and Upavisa classification. They are useful in rasakarma and rasabandhana. Rasamanjari, Rasendrachintamani, Rasa jala nidhi have explained 18 kanda visha. They are- Kalakuta, Saktuka, Vatsanabha, Shringika, Mustaka, Halahala, Haridra, Mayura, Binduka, Sunama, Shankhanabha, Sumangala, Pushkara, Bhramara, Karkotaka, Shuklakanda, Raktashringi, Visha or Chakra.
-# '''Sadharana rasas''': It is explained only by Rasaratnasamuchaya.<ref name=":9" /> They are Kampillaka (Mallotus philippinesis Muell-arg), Gouripashana (Arsenious oxide; As2O3), Navasadara (Ammonium chloride; NH2Cl), Kapardika (Cowries), Agnijara (Amber), Girisindura (Red oxide of mercury; HgO), Hingula (Cinnabar; HgS), Mruddarashringa (Litharge; PbO).
+# '''Sadharana rasas''': It is explained only by Rasaratnasamuchaya.<ref name=":9" /> They are Kampillaka (Mallotus philippinesis Muell-arg), Gouripashana (Arsenious oxide; As<sub>2</sub>O<sub>3</sub>), Navasadara (Ammonium chloride; NH<sub>2</sub>Cl), Kapardika (Cowries), Agnijara (Amber), Girisindura (Red oxide of mercury; HgO), Hingula (Cinnabar; HgS), Mruddarashringa (Litharge; PbO).
 According to tradition, the maharasas and the uparasas are classified in the order in which they find their usefulness with reference to mercury (rasendra). There is also a view that mercury alone has the appellation of rasa, and all the others are called uparasas. Some of the texts differ from one another in the number of maha- and uparasas as well as the substances comprising them. While the Rasaratnasamuccaya gives the above classification, the Rasaprakasasudhakara, considers rajavarta (lapis lazuli) as a maharasa in the place of capala.

@@ Line 163: / Line 163: @@
 === Dyes, Mordants and Pigments ===
-Main article
+{{Main article|Chemistry of Dyeing (रञ्जनम्)}}
 Archeological and literary evidences prove that the art of dyeing was practiced since early days of Indian civilization. A dye is a colored substance which imparts more or less permanent color to other materials. Colored substances usually organic chemical compounds were used for textile dyeing. Dyes which are prepared in the form of powder, paste or solution are utilized generally in coloring cotton, wool, silk and cloth of natural fibres, in cosmetics and manufacture of ink etc. Many soluble dyes are converted into pigments by forming insoluble salts (ex - by replacing sodium in a dye salt with calcium) for use in lacquers, paints etc. Dyes were also used for artificial coloring of food items and soft drinks. They are also used for coloring hair, fur, metals etc.

@@ Line 168: / Line 168: @@
 === Glass Industry ===
-Main article Glass (काचः)
+{{Main article|Glass (काचः)}}
 Generally, glass is produced by melting a mixture of silica (sand: about 75%), soda (about 15%) and calcium compound (lime: about 10%) with the desired metallic oxides that serve as coloring agents.<ref>Story of Glass in India & the World by Pankaj Goyal</ref> Origin of glass is shrouded in mystery and scholars note that it is difficult to pinpoint the exact period. Modern archeological evidence proved that Mesapotamia, Egypt and India made various siliceous and glazed materials including faience (glazed siliceous ware), glazed pottery and glass.<ref name=":8" />
 == Chemistry in Minerals and Metals ==
 Many processes involved in extraction of metals from ores to their purification deal with advanced knowledge of chemistry. Many ancient and medieval texts reveal that people had this knowledge as outlined below.<ref name=":2" /><ref name=":4" />

@@ Line 8: / Line 8: @@
 Rasayana Shastra (Samskrit: रसायनशास्त्रम्) referred to the subject of Chemistry based on the chemical activities involved in biological and inorganic processes. It was also called Rasatantra, Rasa Kriya or Rasa Vidya roughly translating to 'Science of Liquids'. "Rasa" in ayurvedic terminology refers to mercury and [[Rasashastra (रसशास्त्रम्)|Rasashastra]] exclusively deals with the treatment using mercury and its compounds. It is well known that science and technology in ancient and medieval India covered all the major branches of human knowledge and activities, including mathematics, astronomy, physics, chemistry, medical science and surgery etc.
 Chemistry is the study of elements present in the universe which involves the nature of the elements, their occurrence, their physical and chemical properties, their compounds, reactivity, uses and applications. Ancient samskrit literary works supported by the archaeological excavations all over the nation have proved the development of this science as early as the vedic period. The earliest evidence of chemical knowledge possessed by the ancient Indians in the  prehistoric age has been brought to light by the findings of archaeological excavations in Baluchistan, Sindh and Punjab. The ruins of the Indus Valley Civilization that have been unearthed at in these areas furnish much information about the chemical knowledge acquired by the Indus Valley people, particularly with reference to the practical arts like pottery, brick-making, and extraction and working of metals.<ref name=":1">Ray, P. (1956) ''History of Chemistry in Ancient and Medieval India, incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray.'' Calcutta: Indian Chemical Society</ref>
 The findings testify to the facts that the people in the remote ages were acquainted with the art of making painted potteries as well as with the preparation and working of metallic copper. Prafulla Chandra Ray was a renowned researcher of chemistry, who set up several chemical industries in Bengal and is regarded as the "Father of Indian Chemistry" in modern times.
@@ Line 22: / Line 22: @@
 Ancient India's contribution to science and technology include principles of chemistry which did not remain abstract but found expression in practical activities like fermentation processes, distillation of perfumes, aromatic liquids, manufacturing of dyes and pigments and extraction of sugar, extraction of oil from oilseeds, and metallurgy which has remained an activity central to all civilizations from the earliest ages. Archaeologists' findings of the Indus valley civilization showed a well developed urban system with public baths, streets, granaries, temples, houses with baked bricks, mass production of pottery and even a script of their own which depicted the story of early chemistry.<ref name=":0">Purwar, Chhavi. ''[https://www.journalijdr.com/sites/default/files/issue-pdf/7278.pdf Significant Contribution of Chemistry in Ancient Indian Science and Technology.]'' International Journal of Development Research Vol. 06, Issue, 12, pp.10784-10788, December, 2016</ref>
-In pottery making chemical processes were carried out in which materials were mixed, fired and moulded to achieve their objective. In the Rajasthan desert many pottery pieces of different shapes, sizes and colours were found. At MohenjoDaro it was found that for the construction of a well, gypsum cement had been used which contained clay, lime, sand and traces of Calcium Carbonate (CaCO3) and was light grey in colour. Burnt bricks were manufactured on a large scale for making houses drains, boundary walls, public bath etc. Many useful products invented were plasters, hair washes, medicinal preparations etc. which had a number of minerals in them and were used by Indus Valley people.
+In pottery making chemical processes were carried out in which materials were mixed, fired and moulded to achieve their objective. In the Rajasthan desert many pottery pieces of different shapes, sizes and colours were found. At Mohenjo-Daro it was found that for the construction of a well, gypsum cement had been used which contained clay, lime, sand and traces of Calcium Carbonate (CaCO3) and was light grey in colour. Burnt bricks were manufactured on a large scale for making houses drains, boundary walls, public bath etc. Many useful products invented were plasters, hair washes, medicinal preparations etc. which had a number of minerals in them and were used by Indus Valley people.
 Copper utensils, iron, seals, gold and silver ornaments, and terracotta discs and painted grey ware pottery have all been found in thirty five archaeological sites in North India. Scientific dating of these artifacts corresponds to the non-aryan invasion model of Indian antiquity.<ref name=":0" />
-Thus the major chemical products that developed gradually over various eras can be summarized as glass, bricks and pottery, paper, soap, ink, dyeing, cosmetics and perfumes, alcoholic beverages, food processing, pharmaceuticals,  mining techniques and alloy preparations, gun powder and saltpetre, and oilseeds.
+Thus the major chemical products that developed gradually over various eras can be summarized as glass, bricks and pottery, paper, soap, ink, dyeing, cosmetics and perfumes, alcoholic beverages, food processing, pharmaceuticals,  mining techniques and alloy preparations, gun powder and saltpetre, and oilseeds. The practical chemists—potters, brewers, dyers, metalsmiths, glassmakers and the like—contributed a great deal to the growth of technology and in no small measure to the economic welfare of the ancient communities. They were noted for their craftsmanship and experimental skills involving many a chemical transformation both qualitative and quantitative, even though they did not appear to have formulated any theoretical knowledge of the chemical transformations.<ref name=":8">Bose, D. M., Sen, S. N., & Subbarayappa, B. V. (1971). A concise history of science in India. New Delhi: Indian National Science Academy. pp. 274</ref>
 == Alchemical Ideas in the Vedas ==
@@ Line 128: / Line 128: @@
 ) Chemical Change (Rāsāyanika Parivartana)
 The first type of change i.e. the Physical Change, is when the nature of the substance undergoes changes due to various reasons for a particular period of time and returns back to its previous state. For example, a piece of Iron forms into magnet after a deep friction (Gharṣaṇa) on the magnet and returns into being a piece of iron after it loses the magnetic effect. In same manner, water turns into ice at the state of high cooling (Himānka) and returns to liquid state after melting. In second type of change i.e. Chemical Change once the nature of the substance changes it cannot be reversed. For example, Milk turns into curd, and iron turns into rust etc.<ref name=":6">Jena, D. (2021). Concept of chemical science in Vedic literature. ''International Journal of Trend in Scientific Research and Development'', ''5''(4), 43. <nowiki>https://www.ijtsrd.com/papers/ijtsrd41144.pdf</nowiki></ref>
 === Yantras ===
-Many Rasashastra texts carefully spell out the layout of the laboratory, with four doors, an esoteric symbol (RASALINGA) in the east, furnaces in the southeast, instruments in the northwest, etc.
+Many Rasashastra texts carefully spell out the layout of the laboratory, with four doors, an esoteric symbol (RASALINGA) in the east, furnaces in the southeast, instruments in the northwest, etc termed as Rasashala.
 == Traditional Chemical Practices in India ==
@@ Line 137: / Line 149: @@
 # Ayurvedic Preparations: medical preparations including purificatory processes of mercurial compounds involved chemical reactions and apparatuses are discussed in [[Rasashastra (रसशास्त्रम्)|Rasashastra]] and [[Rasayana (रसायनम्)|Rasayana]].
 # Chemical arts and crafts: they include the following
-## '''Pottery''': Involves prolonged heating, fusion, evaporation, and treatment of minerals and pigments for coloring and art.
+##'''Pottery''': Involves prolonged heating, fusion, evaporation, and treatment of minerals and pigments for coloring and art.
 ## '''Bead and Glass making''': Glass is a solid fused mixture of lime, alkali, sand and metallic oxides. They were coloured by adding colouring agents like metal oxides. The Ramayana, Kautilya's Arthashastra, Brihatsamhita mention glass being used. Evidences of glass slag and glazing are found in Hastinapur, Takshila, Nevasa Kolhapur, Maheshwar and Paunar.<ref name=":0" />
 ## '''Jewellery making'''
@@ Line 156: / Line 168: @@
 === Glass Industry ===
-Manufacture of glass and coloured glass is well documented in ancient literature such as Ramayana (2.90.27), Mahabharata and ancient poetic works even though no glass objects have been recovered from Indus valley areas. Kautilya in his Arthashastra while laying down rules for the Superintendent of the treasury talks about the identification of various kinds of gems and precious stones and mentions a few times about glass; in the context of testing gems to place them in jewelry, in trade and tax payments, robbery and fines.<ref>Krishnamurthy. Radha, (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D.'' New Delhi: Indian National Science Academy. (Chapter Dyes, Mordants and Pigments: Page 300 - 312)</ref>
+Main article Glass (काचः)
 == Chemistry in Minerals and Metals ==
 Many processes involved in extraction of metals from ores to their purification deal with advanced knowledge of chemistry. Many ancient and medieval texts reveal that people had this knowledge as outlined below.<ref name=":2" /><ref name=":4" />