Nonmetallc Minerals

A number of Nonmetallic minerals like magnesite, phosphorite, talc, limestone, dolomite, quartz, mica, clay, silica sand, gemstones, decorative and dimension stones, construction materials etc. are known from different parts of the country. Some of the important ones which are explored up to certain stages are briefly described.  

Nonmetallic/ Industrial Minerals

Limestone: Over 1.298 billion metric tons of cement grade limestone deposits are already known from the Lesser Himalayan region only. Exploration of limestone by DMG, in the past was able to identify a number of large to small size limestone deposits. Based on some of the proved limestone deposits few cement industries are already in operation/ production, few others are under construction and quite a few others are in the pipelines. Present domestic cement production could fulfill about 40 - 50% of the total internal demand. 6 new cement industries named Sibom, Sonapur, Ghorahi, Rolpa, Bishal and Nigale cement industries Pvt. Ltd. are under construction and they will start cement production very soon. Therefore, establishment of more cement factories based on own limestone resources is rewarding. Some of the main limestone deposits are Sindhali & Galtar (Udaypur), Bhainse, Okhare and Nibuwatar (Makwanpur), Jogimara & Beldada (Dhadhing), Chovar, Bhattedanda (Llitpur), Balthali & Nandu  (Kavre), Kakaru Khola (Sindhuli), Galtar (Udayapur), Kajeri (Salyan), Nigale (Dhankuta), Chaukune and Lakharpata (Surkhet),  Gandari (Dang), Narapani and Supa Khola (Arghakhanchi), Diyarigad (Baitadi) and few other place in Lalitpur, Kavre, Khotag, Udayapur, Syangja, Palpa, Arghakhanchi, Dang, Pyuthan, Sallyan, Rolpa, Rukum, Bajhang, Baitadi and Darchula districts.  Preliminary studies indicate that there is a possibility to find more than 2.5 billion tons of cement grade limestone deposits only in the Lesser Himalaya. 29 mining licenses and 196 prospecting licenses of limestone have been issued by DMG to private sectors

In many cases Dolomite and limestone occur together. From geological mapping it is known that over 5 billion tons (possible) of dolomite occur mainly in Dhankuta, Khotang, Udayapur, Sindhuli, Dolakha, Kavre, Kathmandu, Makwanpur, Dhadhing, Syangja, Palpa, Baglung, Gulmi, Arghakhanchi, Dang, Pyuthan, Sallyan, Rolpa, Rukum, Jajarkot, Surkhet, Dailekh, Jumla, Achham, Doti, Bajhang, Bajura, Baitadi and Darchula districts in the Lesser Himalayan and in some parts of Higher Himalayan region. Most of them are not yet explored in detail and still do not know their grade and quality to utilize as raw materials for industries.

Phosphorite is one of the main raw materials to manufacture chemical fertilizers like fused magnesium phosphate, triple super phosphate etc. Present annual demand of chemical fertilizer in Nepal is about 150,000mt/ year. Except one or two fertilizer blinding plant no fertilizer plant based in the local phosphatrite minerals exist in the country. Phosphorite (0.7 - 0 4.7m thick bed) is confined to massive cherty and stromatolitic dolomite of Pre-Cambrian to Lower Paleozoic age that occur in Dhik Gad, Junkuna, Morgaon, Sanagaon and Dhaubisaune areas in Baitadi, Far-western Nepal This phosphorite consists of 5–32 % P2O5. Similar (1 to 23m thick) stromatolitic phosphorite band is also traced at Tarugad, Juilgad, Goichan - Kandechaur area in Bajhang and further east to Bajura. Detrital phosphorite fragments (<1mm - 1.5cm) are recorded from Eocene argillaceous limestone lenses and beds in Sewar Khola (Dang) and Mari Khola (Pyuthan). P2O5 content in them is <5% to 10% (Kaphle & Pradhanang 1985). However, the phosphorite fragment itself revealed up to 25% P2O5. Exploration of phosphorite in the vicinity of MBT was able to trace few phosphatic rocks consisting of <5% P2O5. Only few phosphatic nodules/ lenses consist of up to 22% P2O5 in Takure, Barahakshetra, Tawa Khola (Kazitsyn, 1970); Gawar Khola, Sewar Khola in Midwestern Nepal and in Khulia Khola (Kaphle 1997) in Far-Western Nepal.

Magnesite: 180 million tons (66 million tons of high grade, MgO content 88 to 96% loss free basis) of magnesite deposit in Kharidhunga, Dolakha; 20 million tons of mediums to low-grade magnesite deposit in Kampughat in Udayapur district; and few small size magnesite occurrences from Palpa, Baitadi and Dolakha have been identified. Kharidhunga magnesite an open cast mine (Fig.2) has been developed to exploit magnesite as a raw material for Dead Burnt Magnesite (DBM) plant located in Lamosanghu. Some technical problems appeared during test production of DBM.

Talc: Occurrences of talc bands, lenses, veins and pockets are known in magnesite, dolomite and chloritic talc schist in different parts of Lalitpur, Dolakha, Sindhupalchok, Dhadhing, Chitwan, Tanahun, Kaski, Syangja, Surkhet, Bajhang, Bajura, Baitadi and Darchula districts. DMG has issued 25 prospecting and 6 mining license to the private sector. Khari Dhunga talc mine is in operation since more than 2 decade.

Mica: Several but comparatively small occurrences of mica (muscovite and biotite) books are known from different parts of Nepal. But mineable coarse size mica books are recorded only in complex pegmatite Langtang (Rasuwa), Bhumidanda and Kharanetar (Nuwakot), Chaukibhanjyang (Kathmandu), Nibuwagaon (Sindhupalchok), Lekhpatan, Fulbari and Tikachaur (Jajarkot), Khaptad (Bajhang), Baskot and Bhasukan (Doti), Fikal (Ilam), Chilingdin (Panchthar), Rangmale, Akabu/ Sainsabu, Dobal Pokhari, and Khanigaon (Taplejung), Phakuwa and Hyakule (Sankhuwasabha) etc..

Ceramic clay/ Red clay: Irregularly distributed scattered pockets of kaolin are known from Daman (Makwanpur), Panchmane (Kathmandu), Dalchhap and few other places.

Red clay from Panchkhal (Kavre), Lamosure (Hetaunda), Trijuga/ Beltar (Udayapur), Chidika (Arghakhanchi), Guttu (Surkhet) are used in cement factory. Clay from Thimi/ Bhaktpur is used in small-scale pottery industries. Huge amount of siltyclay deposits in different parts of Kathmandu valley is used to manufacture bricks. In villages it is also used in house wall painting. DMG has issued four prospecting and seven mining licenses.

Pyrite is mainly used to extract sulphur and manufacture sulphur compounds e.g. sulphuric acid, ferus sulphate etc. It is rarely used as iron ore where no other iron ore is available. Pyrite is abundantly found in Bering Khola (Ilam), Chhirling Khola (Bhojpur), Pandav Khani (Baglung), Meddi and Bamangaon (Dadeldhura), and many other places mainly in almost all polymetal sulphide deposits.

Silica Sand: About 11.9 million tons of sand suitable for glass industry has been proved in Karra Khola near Hetaunda in Makwanpur district. There is a possibility to find similar sand deposits in similar deposition environment (e.g. in Dudhaura Khola) in other parts of Nepal.

Barites are known from Khanidanada (Pyuthan), Barghare (Makwanpur), Dhokadhunge (Rolpa), Phakuwa (Sankhuwasabha), Urathi, (Baitadi). True picture of barite resource is still unknown.

Graphite is one of the significant mineral in metamorphic terrain in Lesser Himalayan regions. They are reported from Ilam, Dhankuta, Sankhuwasabha, Nuwakot, Sindhupalchok, Dadeldhura etc.

Calcite deposit as such in large size is not identified, however, minor calcite veins and lenses are recorded mainly in carbonate rocks. Calcites are known at few places as stalactite and stalagmite and dog tooh spar in some of the limestone cavities/ caverns. Small scale calcite mine is under development in Nibuwagaon. (Makwanpur).

Diatomite is reported from Chobhar, Thimi Bode and few other places in Kathmandu valley. Small scale mining of diatomite is in operation in Thimi and Bode of Bhaktapur district.

Salt: Brine water that occurs in Narsing Khola (Mustang), Chhiding Khola and Chharkabhot (Dolpa) are tapped and dried for common salt production. Brine water of these area contains 1.5 to 3% NaCl, where as incrustation contains of 72.8% NaCl and 24.5% KCl.