Hutti Gold Mines Limited
Encyclopedia
Hutti Gold Mines Limited (HGML) is a company located in the state of Karnataka
, India
and engaged in the mining
and production of gold
. It was first established as Hyderabad Gold Mines in 1947. It is the only company in India which produces gold by mining and processing the gold ore. Owned by the Government of Karnataka
, HGML has two plants located in Hutti and Chitradurga
. HGML mines gold from its main gold mine located in Hutti
and other satellite mines. It is the first Indian member of the World Gold Council
. Renukacharya, an MLA of the BJP is the Chairman of the company. The executive is headed by Dr.Chandrasekhar IAS and holds the post of Managing Director.
greenstone geological belt which contains both readily extractable native gold and gold-bearing sulphides. HGML consists of two gold units:
These mines in total produce about 3 tonnes of gold a year. With the closure of the Bharat Gold Mines Limited which had operations at Kolar Gold Fields
in Karnataka and at Chittoor district
in Andhra Pradesh
, HGML is the only company in India that produces gold by mining. It has gold ore reserves of about 31.02 million tonnes which could last for about 60 years and yield about 150.4 tonnes of gold.
matrix. However, this method cannot be used to extract gold which is present in sulphides. HGML has made use of advanced technologies like biotechnology
to come up with a cheaper and efficient method to extract gold from sulphides. With the help of the Indian Institute of Science
, Bangalore, an extraction method was devised in which the sulphides were subjected to oxidation using the bacteria
, Thiobacillus ferrooxidans under optimal conditions. The bacteria dissolved the sulphides like pyrite
and arsenopyrite
and thus revealed the native gold. The native gold was then subjected to cyanide leaching to produce pure gold. This method also produces other precious metals like silver
which could be present in the sulphides. After repeated experimentations to come up with the optimal procedure, HGML constructed the first bioreactor
in the middle of 2001.
Karnataka
Karnataka , the land of the Kannadigas, is a state in South West India. It was created on 1 November 1956, with the passing of the States Reorganisation Act and this day is annually celebrated as Karnataka Rajyotsava...
, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and engaged in the mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
and production of gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
. It was first established as Hyderabad Gold Mines in 1947. It is the only company in India which produces gold by mining and processing the gold ore. Owned by the Government of Karnataka
Government of Karnataka
The Government of Karnataka is a democratically elected body with the Governor as the constitutional head. The Governor who is appointed for a period of five years appoints the Chief Minister and his council of ministers...
, HGML has two plants located in Hutti and Chitradurga
Chitradurga
Chitradurga is a town in the southern part of the Indian state of Karnataka. It is also the headquarters of Chitradurga district. Chitradurga was also known by the names Chitradurg, Chitrakaladurga, Chittaldurg. Chittaldrug was the name officially used by the British Govt.-Geography:Chitradurga is...
. HGML mines gold from its main gold mine located in Hutti
Hatti, Raichur
Hatti is a census town in Raichur district in the Indian state of Karnataka. This town is located near Lingusugur taluk, 20km from Lingusugur. Hatti is famous for gold mining as the Hatti Gold Mines-Demographics:...
and other satellite mines. It is the first Indian member of the World Gold Council
World Gold Council
The World Gold Council is a non-profit association of the world's leading gold mining companies, established in 1987 to promote the use of gold. It aims to stimulate demand for gold from industry, consumers, and investors. The Council's Chief Executive Officer is Aram Shishmanian, former head of...
. Renukacharya, an MLA of the BJP is the Chairman of the company. The executive is headed by Dr.Chandrasekhar IAS and holds the post of Managing Director.
Mining
The mines used by HGML are mainly located in the Hutti-Muski precambrianPrecambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...
greenstone geological belt which contains both readily extractable native gold and gold-bearing sulphides. HGML consists of two gold units:
- Hutti Gold Unit: This consists of HGML's main mine located at Hutti and the satellite mines, Uti and Hirabuddini, all of which are located in the Raichur districtRaichur districtRaichur District is an administrative district in the Indian state of Karnataka. It is located in the northeast part of the state and is bounded by Yadgir district in the north, Bijapur and Bagalkot district in the northwest, Koppal district in the west, Bellary district in the south, Anantapur...
. Hutti is an underground mine, Uti is an open-cast mine while Hirabuddini is an exploratory mine. - Chitradurga Gold Unit: This consists of an open-cast mine located in Ajjanahalli in Tumkur districtTumkur districtTumkur district is an administrative district in the state of Karnataka in India. The district headquarters are located at Tumkur. The district occupies an area of 10,598 km² and had a population of 2,584,711, of which 19.62% were urban as of 2001...
and an exploratory underground mine at G. R. Halli in Chitradurga districtChitradurga districtChitradurga district is an administrative district of Karnataka state in southern India. The city of Chitradurga is the district headquarters. Chitradurga gets its name from Chitrakaldurga, an umbrella-shaped lofty hill found there. Tradition dates Chitradurga District to the period of the...
.
These mines in total produce about 3 tonnes of gold a year. With the closure of the Bharat Gold Mines Limited which had operations at Kolar Gold Fields
Kolar Gold Fields
Kolar Gold Fields is a town in Bangarpet Taluk, in the Kolar District of Karnataka state, India. It includes the township of the same name, viz. KGF, where reside mainly the families of the employees of BGML. To the east of KGF is a ridge of hills of which Dod Betta hill, 3195 feet above sea...
in Karnataka and at Chittoor district
Chittoor district
Chittoor District , also known as Chittur, is a district of India's Andhra Pradesh state. The district headquarters is Chittoor City. The district has a population of 4,170,468 according to 2011 census of India. Chittoor district is famous for the Tirupati, Kanipakam and Sri Kalahasti temples...
in Andhra Pradesh
Andhra Pradesh
Andhra Pradesh , is one of the 28 states of India, situated on the southeastern coast of India. It is India's fourth largest state by area and fifth largest by population. Its capital and largest city by population is Hyderabad.The total GDP of Andhra Pradesh is $100 billion and is ranked third...
, HGML is the only company in India that produces gold by mining. It has gold ore reserves of about 31.02 million tonnes which could last for about 60 years and yield about 150.4 tonnes of gold.
Extraction of gold
The process of cyanide leaching is used by HGML to extract native gold which is present in a quartziteQuartzite
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...
matrix. However, this method cannot be used to extract gold which is present in sulphides. HGML has made use of advanced technologies like biotechnology
Biotechnology
Biotechnology is a field of applied biology that involves the use of living organisms and bioprocesses in engineering, technology, medicine and other fields requiring bioproducts. Biotechnology also utilizes these products for manufacturing purpose...
to come up with a cheaper and efficient method to extract gold from sulphides. With the help of the Indian Institute of Science
Indian Institute of Science
Indian Institute of Science is a research institution of higher learning located in Bangalore, India. It was established in 1909.-History:After a chance meeting between Jamsetji N...
, Bangalore, an extraction method was devised in which the sulphides were subjected to oxidation using the bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, Thiobacillus ferrooxidans under optimal conditions. The bacteria dissolved the sulphides like pyrite
Pyrite
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...
and arsenopyrite
Arsenopyrite
Arsenopyrite is an iron arsenic sulfide . It is a hard metallic, opaque, steel grey to silver white mineral with a relatively high specific gravity of 6.1. When dissolved in nitric acid, it releases elemental sulfur. When arsenopyrite is heated, it becomes magnetic and gives off toxic fumes...
and thus revealed the native gold. The native gold was then subjected to cyanide leaching to produce pure gold. This method also produces other precious metals like silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
which could be present in the sulphides. After repeated experimentations to come up with the optimal procedure, HGML constructed the first bioreactor
Bioreactor
A bioreactor may refer to any manufactured or engineered device or system that supports a biologically active environment. In one case, a bioreactor is a vessel in which a chemical process is carried out which involves organisms or biochemically active substances derived from such organisms. This...
in the middle of 2001.