Use: Iron as a single metal and as alloy iron is used in innumerable ways in about every trade and industry and in almost every walk of life. It is used at homes as hundreds of domestic appliances. It is an integral part of all the modern means of transportation, including automobiles, trains, ships, and airplanes. It is use in manufacture of surgical instruments for the health care. Tractors, trolleys, thrashers and other farm machinery are invariably made of iron and its alloys. In construction industry, it is used as iron bars sheets and pipes in many more different ways and in the battlefields, in tanks, guns and rockets, etc.
Ore Deposits: Iron occurs in several kinds of ore deposits. Important ones include: magmatic segregation, contact-metasomatic, replacement, sedimentary, residual and oxidation deposits.
Occurrence in Balochistan: Several iron ore (hematite and magnetite) prospects are known in Chagai district. Occurrences at Chilghazi near Dalbandin, Pachin Koh and Chicken Dik near Nok Kundi and Bandegan near Nok Chah seemingly have considerable potentials.
Important Iron Minerals
Minerals Chemical Iron
Comp Contents
Native
Native iron Fe 100 %
Oxides
Magnetite Fe3O4 72.4%
Hematite Fe2O3 70.0%
Hydrated Oxides
Limonite Fe2O3.nH2O 59 63%
Goethite Fe(OH) 62.9%
Some digging, trenching and drilling was done in the past by the Geological Survey of Pakistan (GSP) and Pakistan Mineral Development Corporation (PMDC) to asses the quality and to evaluate the reserves of these occurrences. Other prospects at Saindak Fort, Mashki Chah, Amir Chah, Durban Chah, Gorband, Kundi-Baluchap and Nok Chah are assessed to have small reserves.
Iron ore prospects in association with hyderothermal mineralization occur in the Shekran and Monar Talar (Gunga) areas in Kalat district where it is hosted in siliceous limestone. The main ore mineral is hematite (Fe2O3) and the reserves are estimated at about 10 million tons. Recently, Abbas and other (1998) of Geological Survey of Pakistan have reported 1 to 7 meters (averaging about 2 meters) thick hematitic sedimentary ironstone bed at the contact of Chiltan Limestone of Jurassic age (150 million years) and Sembar Formation of Cretaceous age (150 - 65 million years) near Johan in Dilband area, Mastung district. Analytical results of 15 samples from the area, according to the authors, indicated presence of 54.03 to 63.66 percent iron oxide (about 35 to 45 percent iron) with low concentration of undesirable elements like sodium, potassium and phosphorous. The reserves have been tentatively estimated at over 200 million metric tons.
Laterite and Bauxite
Laterite, a yellow, light brown, dark brown to maroon and even reddish brown mixture of hydroxides of aluminium, iron, manganese, nickel, often titanium and other metals, is product of surface weathering of rocks in situ in tropical environment. Light brown pisolitic and oolitic laterites and rocks containing high concentration of aluminium are generally called bauxite. Depending upon the chemical composition, laterite may be used as iron, aluminium, nickel, and titanium ores. It is also used in paint industry for preparation of paints and pigments.
Considerably larger laterite occurrences are known in Loralai, Ziarat and Dilband area Mastung and smaller ones in Muslimbagh and Lasbela districts. At Ziarat laterite is exposed at several places around Ziarat town. It occurs in irregular blanket form with thickness varying from 1 to 3 meters and the reserves are estimated at about 15 millions tons. Laterite at Dilband, owing to comparatively high iron contents, is treated as iron ore and was mentioned as iron mineral above.
Lead Minerals
Lead (Pb), a bluish grey soft metal with atomic number, 82; atomic weight, 207.19; specific gravity, 11.34; melting point, 327.4oC; and natural isotopes, 207, 208, 206, and 204; is exceeding rare metal in free state. Out of a number of ore minerals, important ones are Galena, PbS (Pb 80%), Cerusssite, PbCO3 (Pb 77.5 %), Anglesite PbSO4 (Pb 68.3 %), Bournonite, and Wulfremite
Use: Lead is used in storage batteries, cable covering, lead pipe manufacturing, pigments, ammunitions, bearing metals, and casting of a few alloys. Out of a number of lead ores, important ones are galena, cerussite, and wulfremite.
Occurrence in Balochistan: In Chagai galena (PbS) occurs near Ziarat Balanosh in three lenses in a northeast trending 12-ft long and 8-ft wide crushed fault zone in andesite. The deposit was under small-scale mining operation in the past and the mineral was locally consumed. The ore contains 42.5 - 51.3 percent lead and 2.1 - 4.2 percent zinc, and small amount of gold (0.01 - 0.02 oz / ton) and silver (0.95 - 1.44 oz / ton). Mining of the ore was continued up to about 45 feet of depth and thereafter was abandoned probably due to the operational difficulties confronted due crude mining method. Small galena occurrences have also been reported at Koh Marani, about 25 miles northwest of Chagai, at Saindak Koh near Saindak Fort and at Zonk and Zabt areas in Chagai district. An old prospect of the metal, having worked in remote past, occurs at "Surpai" (meaning lead in the local Barahwi language) near Amuri in Chagai district. The senior author briefly visited the prospect several years ago. Apparently no mineralization was noticed at the site but the soil sample collected from floor of the old cave-like working, when chemically analyzed, indicated considerably high lead values (up to 35 percent). If further investigations prove positive, the old working may be reopened.
In Khuzdar and Lasbela districts, lead-zinc ore occur in Shekran, Malikhorn, Gunga, Surmai, Duddar, and Mithi areas. These occurrences, previously known as small prospects after thorough exploration and investigation have proved to be substantially large. Several occurrences of galena are also known in Hunurki River and in Kanrach areas in Lasbela district. The metal in past was mined from the prospects at a small scale but currently preparation of large scale mining is under way.
Price: Price of lead metal in London Metal Exchange in early May, 2008 was U.S. $ 1.15 / Lb.
Magnesium Minerals
Magnesium (Mg) with atomic number 12: atomic weight 24.312; isotopes 24, 25, and 26; melting point 650o C; specific gravity 1.74; averages in ultramafic rocks 20.4%; baslat 4.6%, and granite 0.1%. Major minerals are Magnesite (Mg 28.7%); and Dolomite (Mg 13.8%). Magnesium also occurs in seawater in appreciable concentration (0.13%).
Use: Magnesium is the lightest metal and its alloy with aluminium is used in manufacture of airplanes and automobile bodies and other materials requiring lightness. The metal burns at low temperatures with a strong light and accordingly the metal is used in fireworks and signal flares. Fire-raising bombs are made of Mg 93% and Al 7%.
Ore Deposits: Magnesium does not occur in free-state. It is obtained from natural brine and sea water and from minerals magnesite, dolomite, and brucite.
Occurrences in Balochistan: In Balochistan large deposits of dolomite occur with limestone in the mountain belt that runs from Loralai to Lasbela and beyond. Rich magnesite zones can be demarcated in the belt at several places. Balochistan also has over 700-km long sea coast where magnesium can be extracted from brine and sea water.
Manganese Minerals
Manganese (Mn), atomic number, 25; atomic weight, 54.94, isotope, 55; specific gravity, 7.2; melting point, 1244oC; averages in crustal rocks up to 1000 ppm in mafic rocks, 2200 ppm in felsic rocks and 600 to 850 ppm in soil. Major manganese minerals are: Pyrolusite, MnO2 (Mn 63%); Manganite, Mn2O2.H2O (Mn 62%); Psylomelane, (hydrous oxide) Rhodochrosite, MnCO3 (Mn 47%).
Use: Manganese is used in the manufacture of dry batteries, medical preparations, carbon monoxide gas mask, in dying oils lubricants and in the treatment of chrome leather, pottery and pigments. Metallic manganese is used in casting alloy with copper and aluminium and in making manganese steel, etc.
Occurrences in Balochistan: Several manganese occurrences in association with volcanic rocks are known in at Gadani, Haji Mohammad Khan Bent, Khabri Dhoro, Khan Kheo Nai, Kharri Nai, Kohan Jhal, Saniro, and Siro Dhora in Lasbela district. Estimated ore reserve at Siro manganese deposit, the largest of all these occurrences, contains about 450,000 tons of manganese ore (Master, 1960). In Zhob district, small manganese occurrences are known at Naweoba village near Zhob, and at Waltoi Rud near Nasai. Manganese also occurs at Sotkinoh ridge, west of Tafui peak in the Ras Koh Range and in the Siah Koh Range near Nushki in Chagai district.
Price: Manganese metal in the world markets in 1991 was selling at US $ 4000/ton but recent price of the metal is in not available.
Molybdenum Minerals
Molybdenum (Mo) a minor metal, atomic number, 42; atomic weight, 95.94; isotopes, 98, 96, 92, 95, 97 and 94; specific gravity, 10.2; melting point, 2629oC; averages 1.3 ppm in rocks and 2 ppm in soils. Major mineral of molybdenum is Moylbdenite MoS2 (Mo 60%).
Use: Molybdenum imparts hardness, strength, toughness, and corrosion resistance to the products and therefore its major use is as an alloy in steel. Purified form of molybdenum minerals are used in lubricants that are resistant to high temperature. Molybdenum compounds are used in pigments and as catalysts in petroleum refineries. The metal is also used in electrical and electronic industries.
Occurrence in Balochistan: Molybdenum does not occur in nature in free-state. As sulphide (molybdenite) it occurs with disseminated copper sulphide in porphyry copper deposits. Several porphyry copper occurrences are known in Chagai district, these along with copper, gold and silver, may also be assessed for molybdenum.
Nickel Minerals
Niclel (Ni), atomic number, 28; atomic weight, 58.71; isotopes 58, 60, 61, 62 and 64; melting point, 1455oC; specific gravity, 8.9; average in rocks: 100 ppm in ultramafic rocks, 1200 ppm in felsic 8ppm; 40 ppm in soils. Major minerals are Millerite, NiS (Ni 64.7 %); Nicollite, NiAS (Ni 43.9%); Pentlandite, (Fe,Ni)S; Garnierrite, H2(Ni,Mg)SiO4.nH2O (Ni variable).
No occurrence of nickel has been reported in Balochistan so far, but its presence in the sediments derived from mafic igneous rocks in the Zhob valley and in Khuzdar-Bela districts is highly probable.
Price: Nickel in London Metal Exchange in early May, 2008 was selling at over U.S. $15 per lb.
Platinum Minerals
Platinum (Pt), atomic number 78; atomic weight 195.09; isotopes 190, 192, 194, 195, 196, and 198; melting point 1769o C; specific gravity 21.46; averages to about 0.01 ppm in ultramafic rocks. Chief mineral is native platinum which occurs as placer deposits derived from mafic rocks rich in chromite and nickel. The metal also occurs in compounds as PtAs2, PtAsS, pd3Sb, PtPdNiS. Most platinum, however, is won as a bi-product during other metal’s refining.
Use: Platinum, a metal costlier than gold, is mainly used in jewelry, electrical industry, and in dentistry.
Ore Deposits: Platinum and allied group of metals invariably occurs in association with chromite and nickel in ultramafic and mafic rocks.
Occurrence in Balochistan: No occurrence of Platinum or platinoid metals have so far been reported in Balochistan. In fact the metal has not been specifically looked for in the past. Occurrence in chromite rich sediments derived from ultramafic rock in Muslimbagh-Khanozoi area ultramafic complex and in Khuzdar and Ras Koh areas is highly prpbable.
Silver Minerals
Silver (Ag), atomic number, 47; atomic weight, 107.87; isotopes, 107 and 109; electrical conductivity, lowest of all metals; thermal conductivity, highest of the metals; melting point, 1050; Specific gravity, 10.5; average rock content: mafic, 0.3 ppm; felsic, 0.15 ppm; black shale, 5 – 50 ppm; soil, 0.1 ppm. Major minerals: Native Silver, Ag (Ag 100%); Argentite or Silver Glance, Ag2S (Ag 87.1%); Stephanite, Ag2SbS4 (Ag 68.5%); Ruby Silver – Pyrargyrite, Ag3SbS3 (Ag 59.9%) and Prousite, Ag3AsS3, (Ag 65.4%); Freieslebenite, (Pb,Ag)Sb5S12 (Ag 22-23%); Polybasite, (Ag,Cu)16 (Sb, As)2S11 (Ag 70%); Hessite, Ag2Te (Ag variable); Ceragyrite or Keragyrite or Horn Silver, AgCl (Ag 75.3%).
Use: Silver is used for monetary purposes, photography, jewelry, and silver platings, electrical industry, etc.
Occurrence in Balochistan: Silver occurs in association with copper and gold in copper-silver-gold deposits at Saindak and Rekodiq. Other porphyry copper prospects of Chagai district, as indicated earlier, hopfully contain the metal in appreciable quantities.
Zinc Minerals
Zinc (Zn), atomic number, 30; atomic weight, 65.37; isotopes 64, 66, 67, 68 and 70; melting point, 419.5oC; specific gravity, 7.13; average content in rocks, 10 – 300 ppm; felsic 60ppm; mafic rocks, 130 ppm; black shale, 100 – 1000 ppm; soils 50 ppm. Major minerals are Sphalerite, ZnS (Zn 67%) and Smithsonite ZnCO3 (52%).
Use: Zinc is used for the manufacture of galvanised iron products, like I.G sheets and water pipes, to protect the metal against rusting. It is also used in casting alloys like brass, bronze, German silver, etc. Zinc oxide is used in rubber industry, in making sticking plasters for medical use, and for making zinc white and fluorescent screens, etc.
Occurrences in Balochistan: Zinc often occurs in association with silver, galena (lead ore), copper ore, tin ore, etc., and its independent occurrences are also known. In association with galena, zinc occurs in the Chagai district at Dirang Kalat near Ziarat Balanosh (discussed earlier with lead). Sphalerite (ZnS) a zinc ore, in association with pyrite (FeS) and chalcopyrite (CuFeS2), occurs in Kimri Nala, northeast of Nok Chah, near Bandegan Khaur.
Zinc in association with lead occurs in Khuzdar and Lasbela districts at Shekran, Malikhorn, Gunga, Surmai, Duddar, and Mithi areas. These occurrences have already been mentioned with lead. Chinese mining company MCC is currently working for large scale exploitation of zinc with lead at these deposits, particularly at Duddar.
Price: Zinc metal in London Metal Exchange in early May, 2008 was selling @ US $ 0.97 / lb.
REFERENCES
Abbas S. G., Kakepoto, A. A., Ahmed, M. H., and Khan, A. L., 1998, Iron ore deposit of Dliband area, Mastung district, Kalat Division, Balochistan: Inf. Rel. No. 679, Geol. Surv. Pakistan, 19 p,
Ahmad, M. U., 1986, Dasht-e-Kain Porphyry copper prospect in context of the Metallogeny of Chagai calc-alkaline volcano-intrusive Complex, Chagai District, Balochistan, Pakistan: A Ph. D Thesis submitted to the Faculty of Mining and Geology, Belgrade University, Yugoslavia, 115 p.
Kazmi, A. H., and Abbas, S. G., 2001, Metallogeny and Mineral deposits of Pakistan: Orient Petroleum Incorporation, Islamabad, Pakistan.
Master, J. M., 1960 Manganese showings of Las Bela District, West Pakistan. Geol. Surv. Pakistan, Inf. Release, 13, 16 p.
Razique, A., 2001. Potential of economic porphyry copper-gold deposits in western Chagai magmatic belt, Balochistan: Acta Mineralogica.