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History

The Cultural History of Copper

Copper has played an important role in the development of human civilization. Copper was discovered in several sites, and has notable industrial origins in Cyprus whose name comes from those that traded the metal as a commodity. The ancients represented copper by the symbolic Egyptian hieroglyph meaning “for life,” marking the durability of copper.

It isn’t easy to pinpoint the exact moment of the appearance of the first copper objects. Copper hunting tools and weapons likely appeared around 5000 BC in Mesopotamia. At the time, the metal existed exclusively in nature in its native state.

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The History of Copper

Copper and Civilization

For many civilizations, copper has been a source of inspiration for artists and builders. Soon after its discovery, copper was used in the minting of coins and forging swords. In many countries, copper is still regarded as a precious metal because of its unique properties.

The wealth that copper produces leads to positive change in various ways – most notably in jobs for local communities. Historically, it developed new towns, villages, and settlements. In the creation of jobs, copper attracts new residents and employees.

The Copper Age first started around 5000 B.C. Metal casting in the Near East was a common practice in ancient times. In ancient Egypt, copper statues were made before the copper was available to Europeans. During this period, copper statues enjoyed a high artistic status. Copper jewelry and copper sculptures began to be made in Africa around the 9th century, while Native Americans and First Nations discovered the function and beauty of copper.

China

Until the end of the Shang Dynasty around 1050 BC, China used the mold casting as the sole copper manufacturing method. In this process, an object is reproduced on a model, which is then cast in clay. Once the model has been released from the mold, the pieces are reassembled, but the mold becomes a casting mold after firing. The Jiangnan Copper House stands tall today, housing ancient copper sculptures, ornaments, and tools.

Bronze axe from the Shang Dynasty inlaid with turquoise. c.14th-11 century B.C. – Arthur M. Sackler Museum, Harvard University

Middle East

Modern-day Jordan was the site of ancient mines and smelting sites. These mines may have belonged to King Solomon but while most historians mark this industrial activity after his reign, carbon dating in the last few years has strengthened the case for Solomon’s copper extraction and processing of copper at these sites. This claim is also backed up by biblical scripture which describes Solomon’s reign around 1000 B.C., a time which coincides with dating of ancient copper processing sites. The Bible describes “brass” and “bronze” opulence in Solomon’s court, alloys of copper, let alone copper being understood by scholars as fundamental to King Solomon’s wealth

King Solomon and the Iron Worker by Christian Schussele, 1863 depicts a king’s wealth brass, bronze, and copper

Ancient Greece

In the Mycenaean period, from around 1600 BC to around 1000 BC, Greece was prosperous, and copper was often used for everyday use and works of art.

By the 6th century AD, the lost wax casting technique had gained momentum. The copper sculptures that were produced were often adorned with glass, silver, and copper for realistic features.

It is believed that the statues were mass-produced and not composed of individual pieces by the artist. Some statues from this time that sunk in shipwrecks were recently found. It appears that separately cast torsos could have been attached to already manufactured limbs.

Boxer at Rest by Apollonius of Athens – c.330 to 50 B.C.

Ancient Rome

Several copper statues from various countries were sent to Rome, where they were melted down to recover the copper and make it into Roman weapons or sculptures. In the first century AD, Pliny the Elder wrote about the reuse of copper by Rome in the foundries of Brindisi. Sculptures from a copper age were discovered in 1992 attached to a wreck located in the Mediterranean Sea near Brindisi. The sculptures came from Eastern Mediterranean territories occupied by the Roman Empire between the 4th and 3rd centuries AD.

West Africa

Copper and bronze sculptures, such as breastplates, vases, crowns, and swords, have been discovered from the Igbo-Ukwu civilization. This civilization was one of the first in West Africa to make copper sculptures using the lost wax technique. Extensive work was done by assembling several pieces cast in copper.

Igbo-Ukwu bronze ceremonial staff head. c.9th century

Renaissance Italy

Copper started to appear in sculptures around the 1500s when Florence thrived as the center of the copper craft. The city eventually became famous for its bronze statue, including those by Donatello and Lorenzo Ghiberti. These are among the most iconic figures of the Renaissance. Sculptors such as Michelangelo, among others, drew inspiration from Donatello.

David by Donatello in bronze – c.1450

The Americas

Mexico

In the mid-15th century, the Purepecha peoples from central Mexico began producing hammered copper sculptures. In 1804 the Spanish established foundries in Mexico, which continue today to produce copper sculptures.

They used the heating and hammering technique to make tools and ornaments. In the process, copper is heated till it can be hammered several times. The patterns and soot are added to the part using special hammers. What is left becomes a red patina.

The Museo Nacional del Cobre (National Copper Museum) – Santa Clara del Cobre, Mexico

Northwest

Indigenous peoples of the region are known to have used copper for payment, and symbolic significance and was generally the property of chieftains but were connected to Shamans. During the Potlatch, a ceremonial feast among indigenous peoples to display wealth and establish status and social prestige, copper was sometimes used in place of slaves among historic indigenous peoples. Copper would be destroyed as part of the ceremony to display the wealth of chieftains. As an indicator of value, copper was an important element in the succession ceremonies for these leaders. Rival chiefs would symbolically break their copper in exchange with other chiefs until one’s copper was fully broken into pieces, symbolizing defeat. In the tradition of indigenous peoples, copper was also important in funerals and weddings.

The Old Copper Complex refers to the ancient copper culture of Native Americans-the original inhabitants of the Great Lakes region. This culture reportedly spans many thousand years in an area of thousands and thousands of square miles.

Today tangible evidence suggests these communities used copper to produce countless tools in the Middle Archaic period. They got their copper from natural ores that ran hundreds of miles along the Keweenaw Peninsula.

Their copper was the purest, over 95%. Researchers conclude that large amounts of this pure copper must have been used for ornaments and weapons by the Native Americans from the extent of mining. Significant artifacts, including axes and adzes, knives, and harpoons, have been found.

Copper knife, apud, spearpoints, and awls. c.3000-1000 B.C.

Religious Significance of Copper

For more than 5000 years, copper has been linked to the goddess of love (Aphrodite). Copper was also by the Egyptians used to purify water and keep wounds clean. Shamans believe that copper magnifies energy transfer, meaning that the wearer can absorb healing provided by the minerals or crystals.

Some of the copper craftwork found in Egyptian tombs remains today, including copper plumbing pipe, even though it is thousands of years old. Burying everything that a person would need in the next world in the tombs, ancient Egyptians used bronze to make models of statues, bakehouses, tanneries, breweries, and boats.

Much of the history, processing, and use of copper that we know today only survived because of representation in Christian monastic and Islamic cultural writings. Three famous writers Peter Theophilus in the 11th century, Georgius Agricola in the 16th century, and Johannes Mathesius in the 17th century, describe in detail the metal producing techniques of their times.

This literature has influenced much of modern mining uses of copper in society.

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Mining facts

Magnetite and Magnetite Mining in Canada

Magnetite (also magnet iron, magnet iron stone, iron oxide, or iron (II, III) oxide) is the most stable iron oxide with high resistance to acids and alkalis. It has a cubic crystal system and a chemical molecular formula Fe3O4. One of the iron ions is divalent. The other two are trivalent, so Magnetite is also referred to as iron (II, III) oxide. It has a ‘Mohs’ hardness of 5.5 to 6.5, a black color, a line color, and a matte metallic sheen.

Crystal structure of magnetite: oxygen (gray), divalent iron (green), trivalent iron (blue), iron ion in octahedron gap (light blue octahedron), iron ion in tetrahedron gap (gray tetrahedron) – Wikimedia commons

History of magnetite mining

Magnetite is one of the most powerful magnetic minerals. When the temperature falls below 578°C, the magnetization is mostly aligned in the earth’s magnetic field direction. A remnant magnetic polarization of the order of magnitude 500 nT results. In this way, magnetite crystals can preserve the direction of the earth’s magnetic field at the time of their formation.

The investigation of the direction of magnetization of lava rock (basalt) led geologists to observe that in the distant past, the magnetic polarity of the earth must have reversed from time to time. Due to its excellent magnetic properties, Magnetite is still used today in the construction of compasses. As a color pigment, it bears the name iron oxide black.

The name magnet emerged from the Latin name form magnetem (from nominative magnes – magnet). The medieval mineral name Magneteisenstein and the name Magnetit were introduced by Wilhelm Haidinger in 1845.

According to Greek legend, the shepherd Magnes is said to have been the first to find a natural stone with magnetic properties. The shepherd found the stone on Mount Ida when his shoe-heel stuck to the ground.

Magnetite is magnetic!

Another possible origin of the name refers to the Greek landscape Magnesia. Georgius Agricola (1494-1555) used the term “magnetic stone” in his well-known work De Re Metallica in 1550 as an ingredient for glass production.

The reference to the stone magnes, named after a shepherd of the same name, can be found in works by the Roman writer Pliny, the Elder. Pliny distinguished two types of magnes; a “male” and a “female,” of which only the male had the power to attract iron and thus corresponded to the actual Magnetite. “Female” magnesite was probably manganese ore, similar to the “male” in appearance.

Illustration of Magnes the shepherd

The mineral might have also been named after Magnesia, a landscape in Thessaly or the city of Magnesia. It is also possible that the name Magnetite comes from other Greek or Asia Minor places of the same name, in which iron ore chunks with magnetic properties were found over 2500 years ago.

Occurrence

Magnetite occurs in solid or granular form and also as crystals. The latter are often octahedral in shape, so each has eight triangular boundary surfaces. It is a ubiquitous mineral, but it is rarely the main component of an iron rock.

Magnetite
Magnetite

Magnetite is found in numerous igneous rocks such as basalt, diabase, and gabbro in metamorphic rocks. Its hardness means that Magnetite remains intact as sand in river sediments despite weathering processes.

Most of the Canadian Magnetite comes from the Labrador Trough region, on the border between Newfoundland and Quebec and Labrador. Vast deposits of Magnetite can be found in Nunavut, Faraday Township, Hastings County, Ontario, and Outaouais, Québec, Canada. Magnetite deposits are mined in British Columbia at Mount Polley.

Magnetite Uses

Dense Media Separation

Magnetite can be used in industry as a giant magnet. This has applications for sorting valuable materials from others in order to extract value. Those that panned for gold used pans, water, and agitation to remove dirt and debris from valuable nuggets of the valuable ore. Recyclers use magnetite in huge magets to sort valuable scrap metal from less valuable material. Magnetite mining helps the world extract value in an efficient way, whether from raw material or to repurpose discarded material in a green and environmentally friendly manner.

Dense Media Separation has its origins in cleaning coal. Finer coal material is separated from impurities making the energy derived from coal mining cleaner and more efficient.

Dense Media Separation is used in recycling industries to sort scrap metal. This is useful to give valuable material new life in everyday products from smartphones to electric vehicles. Magnetite makes recycling much more efficient, reducing the market price for recycled metals, allowing it to compete with newly mined metals in manufacturing.

Scrap metal recycling

Potash mining is a significant industry in Canada, particularly in the province of Saskatchewan. Potash is primarily used in fertilizer to more cheaply and efficiently feed a hungry world. Magetite, through the process of dense media separation, is used to purify extracted potash. Potash is a mixture of potassium chloride (KCl) and sodium chloride (NaCl). Magnetite is used in dense media separation in the potash extraction to remove NaCl from solution, leaving the valuable KCl behind.

Potash mining

Electrical industry

Along with hematite, Magnetite is one of the essential iron ore. At 72 %, iron has the highest content of this metal. The term iron oxide black means finely ground Magnetite.

Magnetite plays an essential role in the electrical industry. The occurrence of magnetic ores in rocks such as Magnetite or ulvite enables geological studies to be carried out on the earth’s magnetic field orientation.

Due to the 100 % spin polarization of the charge carriers predicted by theory, Magnetite is also traded as a hot candidate for spin valves in spin electronics.

As a building material

Magnetite is used in the construction industry as a naturally granular aggregate with a high bulk density (4.65 to 4.80 kg/dm 3 ) for heavy concrete and structural radiation protection. Thanks to the heavy mineral, the building material can help to attain a solid concrete density of more than 3.2 t/m3; and is helpful in the construction of hospital radiology units. 

Radiation protection concrete achieves a shielding function through its mass, but an aggregate with radiation-absorbing properties such as Magnetite increases the protective effect. 

Magnetite in jewelry

Classic jewelry clasps are often extremely filigree and, therefore, difficult to close. Magnetic jewelry clasps provide a remedy; they enable necklaces and bracelets to be easily closed. The strong magnets ensure a firm hold. To open the chain or strap, wearers simply have to slide two locking parts sideways.

Wearing jewelry is helped by magentic clasps

Heat storage

Industries use natural iron oxide minerals because they can keep the heat very efficiently. They use Magnetite in heat blocks in night storage heaters. Magnetite facilitates more extensive storage of thermal heat much more sustainably compared to other materials.

Magnetite is used in foundry metal protection

The mineral helps to prevent surface defects in metal fixtures in foundries. Natural mineral magnetite where it crashed into a pure, dry, and fine powder that’s used to protected casted metals.

Magnetic therapeutic beliefs in ancient times

Magnetism has been used traditional therapies for thousands of years, though modern science disputes therapeutic effect in placebo trials. The Greeks used magnetism in ancient treatments in 5th century BC. In China, magnets have been integrated into traditional therapy for over 2000 years, magnetism was also in traditional therapeutics in India and ancient Egypt to heal broken bones and other ailments.

Hippocrates described their healing power in the same way as the legendary doctor Paracelsus, who recommended treatments with magnets. Even during this time, women and men wore jewelry made from magnetic ores.

In ancient times magnetite mining became a major economic activity in the Thessalian city of Magnesia. Today, like the ancient Greeks, Canada has a reputation as a leading mining nation with the minerals sector as a core part of the economy. Magnetite mining supports jobs and increases economic growth in provinces and territories where it is mined along with broader benefits to Canada’s national economic output.