Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron, copper, silver, tin, lead and zinc. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal behind. The reducing agent is commonly a fossil-fuel source of carbon, such as carbon monoxide from incomplete combustion of coke—or, in earlier times, of charcoal. The oxygen in the ore binds to carbon at high temperatures, as the chemical potential energy of the bonds in carbon dioxide is lower than that of the bonds in the ore.
Copper is a chemical element; it has symbol Cu and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.
Bangka is an island lying east of Sumatra, Indonesia. It is administered under the province of the Bangka Belitung Islands, being one of its namesakes alongside the smaller island of Belitung across the Gaspar Strait. The 9th largest island in Indonesia, it had a population of 1,146,581 at the 2020 census; the official estimate as at mid 2023 was 1,191,300. It is the location of the provincial capital of Pangkal Pinang, and is administratively divided into four regencies and a city. The island itself and the surrounding sea suffers considerable environmental damage from its thriving tin mining industry which operates on- and offshore.
Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper ores consists of a series of physical, chemical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.
The Southeast Missouri Lead District, commonly called the Lead Belt, is a lead mining district in the southeastern part of Missouri. Counties in the Lead Belt include Saint Francois, Crawford, Dent, Iron, Madison, Reynolds, and Washington. This mining district is the most important and critical lead producer in the United States.
Mining in Cornwall and Devon, in the southwest of Britain, is thought to have begun in the early-middle Bronze Age with the exploitation of cassiterite. Tin, and later copper, were the most commonly extracted metals. Some tin mining continued long after the mining of other metals had become unprofitable, but ended in the late 20th century. In 2021, it was announced that a new mine was extracting battery-grade lithium carbonate, more than 20 years after the closure of the last South Crofty tin mine in Cornwall in 1998.
Arsenical bronze is an alloy in which arsenic, as opposed to or in addition to tin or other constituent metals, is combined with copper to make bronze. The use of arsenic with copper, either as the secondary constituent or with another component such as tin, results in a stronger final product and better casting behavior.
A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, niobium, rhenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as the gold group and the platinum group. Among the alloys found in native state have been brass, bronze, pewter, German silver, osmiridium, electrum, white gold, silver-mercury amalgam, and gold-mercury amalgam.
Silver mining is the extraction of silver by mining. Silver is a precious metal and holds high economic value. Because silver is often found in intimate combination with other metals, its extraction requires the use of complex technologies. In 2008, approximately 25,900 metric tons of silver were consumed worldwide, most of which came from mining. Silver mining has a variety of effects on the environment, humans, and animals.
Mining was one of the most prosperous activities in Roman Britain. Britain was rich in resources such as copper, gold, iron, lead, salt, silver, and tin, materials in high demand in the Roman Empire. Sufficient supply of metals was needed to fulfil the demand for coinage and luxury artefacts by the elite. The Romans started panning and puddling for gold. The abundance of mineral resources in the British Isles was probably one of the reasons for the Roman conquest of Britain. They were able to use advanced technology to find, develop and extract valuable minerals on a scale unequaled until the Middle Ages.
In the United States, copper mining has been a major industry since the rise of the northern Michigan copper district in the 1840s. In 2017, the US produced 1.27 million metric tonnes of copper, worth $8 billion, making it the world's fourth largest copper producer, after Chile, China, and Peru. Copper was produced from 23 mines in the US. Top copper producing states in 2014 were Arizona, Utah, New Mexico, Nevada, and Montana. Minor production also came from Idaho and Missouri. As of 2014, the US had 45 million tonnes of known remaining reserves of copper, the fifth largest known copper reserves in the world, after Chile, Australia, Peru, and Mexico.
South Crofty is a metalliferous tin and copper mine located in the village of Pool, Cornwall, England. An ancient mine, it has seen production for over 400 years, and extends almost two and a half miles across and 3,000 feet (910 m) down and has mined over 40 lodes. Evidence of mining activity in South Crofty has been dated back to 1592, with full-scale mining beginning in the mid-17th century. The mine went into serious decline after 1985 and eventually closed in 1998. After several changes of ownership, South Crofty is owned by Cornish Metals Inc, which is working to re-open the mine, as of November 2022, having received a permit for dewatering the mine.
Oxhide ingots are heavy (20–30 kg) metal slabs, usually of copper but sometimes of tin, produced and widely distributed during the Mediterranean Late Bronze Age (LBA). Their shape resembles the hide of an ox with a protruding handle in each of the ingot’s four corners. Early thought was that each ingot was equivalent to the value of one ox. However, the similarity in shape is simply a coincidence. The ingots' producers probably designed these protrusions to make the ingots easily transportable overland on the backs of pack animals. Complete or partial oxhide ingots have been discovered in Sardinia, Crete, Peloponnese, Cyprus, Cannatello in Sicily, Boğazköy in Turkey, Qantir in Egypt, and Sozopol in Bulgaria. Archaeologists have recovered many oxhide ingots from two shipwrecks off the coast of Turkey.
Metals and metal working had been known to the people of modern Italy since the Bronze Age. By 53 BC, Rome had expanded to control an immense expanse of the Mediterranean. This included Italy and its islands, Spain, Macedonia, Africa, Asia Minor, Syria and Greece; by the end of the Emperor Trajan's reign, the Roman Empire had grown further to encompass parts of Britain, Egypt, all of modern Germany west of the Rhine, Dacia, Noricum, Judea, Armenia, Illyria, and Thrace. As the empire grew, so did its need for metals.
Mining in the United Kingdom produces a wide variety of fossil fuels, metals, and industrial minerals due to its complex geology. In 2013, there were over 2,000 active mines, quarries, and offshore drilling sites on the continental land mass of the United Kingdom producing £34bn of minerals and employing 36,000 people.
Tin is an essential metal in the creation of tin-bronzes, and its acquisition was an important part of ancient cultures from the Bronze Age onward. Its use began in the Middle East and the Balkans around 3000 BC. Tin is a relatively rare element in the Earth's crust, with about two parts per million (ppm), compared to iron with 50,000 ppm, copper with 70 ppm, lead with 16 ppm, arsenic with 5 ppm, silver with 0.1 ppm, and gold with 0.005 ppm. Ancient sources of tin were therefore rare, and the metal usually had to be traded over very long distances to meet demand in areas which lacked tin deposits.
Copper metallurgy in Africa encompasses the study of copper production across the continent and an understanding of how it influenced aspects of African archaeology.
Non-ferrous extractive metallurgy is one of the two branches of extractive metallurgy which pertains to the processes of reducing valuable, non-iron metals from ores or raw material. Metals like zinc, copper, lead, aluminium as well as rare and noble metals are of particular interest in this field, while the more common metal, iron, is considered a major impurity. Like ferrous extraction, non-ferrous extraction primarily focuses on the economic optimization of extraction processes in separating qualitatively and quantitatively marketable metals from its impurities (gangue).
China Hongqiao Group Limited is a company founded in 1994 that specializes in the production of aluminium. Hongqiao is currently the second largest aluminium producer in the world after Chinalco. It is listed on the Hong Kong Stock Exchange with stock code 1378, and is incorporated in George Town, Cayman Islands.
Bauxite has been mined in Indonesia since the Dutch colonial era.
