Sunday, May 16, 2021

What is an Ore?

Ore 

Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit. Ore is extracted from the earth through mining and treated or refined, often via smelting, to extract the valuable metals or minerals. The grade of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining, and is therefore considered an ore.

Minerals of interest are generally oxidessulfidessilicates, or native metals such as copper or gold. Ores must be processed to extract the elements of interest from the waste rock. Ore bodies are formed by a variety of geological processes generally referred to as ore genesis.

Ore deposits

An ore deposit is an economically significant accumulation of minerals within a host rock. This is distinct from a mineral resource as defined by the mineral resource classification criteria. An ore deposit is one occurrence of a particular ore type. Most ore deposits are named according to their location (for example, the Witwatersrand, South Africa), or after a discoverer (e.g. the Kambalda nickel shoots are named after drillers), or after some whimsy, a historical figure, a prominent person, something from mythology (phoenix, kraken, serepentleopard, etc.) or the code name of the resource company which found it (e.g. MKD-5 was the in-house name for the Mount Keith nickel sulphide deposit).

Classification

Granite related hydrothermal

  • Intrusive-related copper-gold +/- (tin-tungsten), typified by the Tombstone, Arizona deposits.
  • Hydromagmatic magnetite iron ore deposits and skarns.
  • Skarn ore deposits of copper, lead, zinc, tungsten, etcetera.

Magmatic deposits

  • Magmatic nickel-copper-iron-PGE deposits including
  • Cumulate hard-rock titanium (ilmenite) deposits

Volcanic-related deposits

A cross-section of a typical volcanogenic massive sulfide (VMS) ore deposit

  • Examples include Teutonic Bore and Golden Grove, Western Australia.
  • Kuroko type.

Metamorphically reworked deposits

  • Broken Hill Type Pb–Zn–Ag, considered to be a class of reworked SEDEX deposits

Carbonatite-alkaline igneous related

Sedimentary deposits


Hydrothermal deposits formed by basinal saline fluids, include the following main groups: 

  • Sediment-hosted stratiform Cu-Co-(Ag) deposit, typified by the Copperbelt of Zambia and DRC.

Astrobleme-related ores

Important ore minerals


What is a METALLURGY and history of METALS?

What is a METALLURGY?
Metallurgy is study of science and technology concerned with properties, production and purification of metals. It is an art of extracting metals from ores and modifying them for use.
The extraction and isolation of metals from ores:
  • Concentration of the ore.
  • Isolation of the metal from its concentrated ore.
  • Purification of the metal.
History
No substance has been as important as metal in the story of man's control of his environment. Advances in agriculture, warfare, transport, even cookery are impossible without metal. So is the entire Industrial Revolution, from steam to electricity.


Throughout history, man has harnessed the power of metals to make tools, steel buildings, instruments of war, aid in medicine and create innovations that have advanced humankind. The common metals copper, lead, iron, tin and aluminum have been central to these innovations. Each with their own unique history, these five common metals changed civilizations, funded empires and have become a part of our everyday lives.

Copper

Copper, a soft and malleable metal, has been used for at least 10,000 years. First discovered around 9000 BC in the Middle East, knowledge of copper smelting spread around the world to China around 2800 BC, Latin America before 600 AD and in Sub-Saharan Africa around 900 AD. The extraction of copper was essential to the discovery of other metals, such as iron and bronze.
               As early as 3000 BC, Sumerians and Egyptians were using copper alloyed with tin to create bronze. The metal was a vital resource for both Greeks and Romans. Known by the Romans as "cyprium," the metal was named after the island of Cyprus, where the majority of Roman copper was mined. Later, the term was modified to become "cuprum," the basis of the English term "copper." The metal was used as currency throughout the Roman Empire from the 6th through 3rd centuries BC, with the faces of emperors imprinted on each coin. Associated with Venus and Aphrodite, the goddesses of love, copper was revered for its beautiful warm color and luster.
               Use of copper spread around the world in the following centuries. Brass, an alloy of tin and copper, was discovered in the British Isles during the 3rd century BC and copper extraction began in North America around 800 AD. In 1830, German chemist Gottfried Osann developed a powder metallurgy technique that revolutionized the use of copper in manufacturing. The next major innovation occurred in 1949, when the Finnish company Outokumpu invented a flash smelting process that rapidly accelerated the production of copper.
               Today, the majority of copper is used in electrical wires, roofing, machinery and plumbing. 5% of the world's copper is currently used in combination with brass or bronze to create a more resilient alloy.

Lead

Like copper, lead is a malleable metal with a history spanning centuries. Widely available and simple to extract, the metal was The earliest known lead artifacts, beads found in the Catalhoyuk region of what is today Turkey, date back to 6400 BCE. The Roman Empire was the largest producer of lead in the ancient world. Romans produced nearly 80,000 metric tons of the metal annually through their mining endeavors in Central Europe, the Balkans, Asia Minor, Greece and the British Isles. The mines in Hispania were particularly active, producing nearly 40% of all lead at the time.
             Lead was used by the Romans in the construction of monuments, statues and buildings. The metal was formed into pins used to secure limestone bricks. Associated with the planet Saturn by alchemists whose main goal was to turn lead into gold, the metal was believed to be the oldest metal and was symbolized by a scythe. Centuries later in 1951, Nobel Laureate chemist Glenn Seaborg succeeded in turning a small quantity of lead into gold.
             The metal's abbreviation "Pb" stems from the Latin "plumbum," meaning "soft metal." The modern English terms "plumber" and "plumbing" stem from this root as well. Today, lead is widely used in plumbing, bullets, batteries and in numerous alloys.

Iron

 The development of iron ore and its resulting innovations gave rise to Celtic expansion in Europe and aided in the growth of the Roman Empire. Centuries later, British chemist Henry Cort's discovery of the process to create wrought iron and Abraham Darby's invention of a blast furnace which created cast iron helped spark the Industrial Revolution during the late 18th century.
Iron is still the most commonly used metal today. Different types of the metal are used to create stainless steel, ammonia, paint, circuit boards and other objects used in modern daily life.
             Today, most of the world's tin originates from Bolivia, the Republic of the Congo, China, Thailand, Indonesia and Malaysia. Tin is used in many common objects like cans, kitchen utensils, decor, wrappings, circuits and even toothpaste.
Danish chemist Hans Christian Orested built on the work of Moveau and Davy who first isolated aluminum in 1825. Two years later, German chemist Friedrick Wohler discovered aluminum after creating the metal by mixing anhydrous aluminum chloride and potassium.
Before improvements made by Charles Martin Hall and Paul Heroult in the late 1880s, aluminum's very difficult extraction process made the metal more costly than gold. Aluminum was still more valuable than silver when it was chosen to top the Washington Monument in 1884.
Thanks to additional innovations in processing, aluminum is more affordable and very common. The metal is now used in a variety of ways, such as in consumer products, glass, packaging, transportation, windows, gutters, kitchen utensils and outdoor furniture.
These five common metals have revolutionized the way people work, travel, build homes, and spend their leisure time. Their long histories from simple ores to complex machines and objects are a testament to mankind's innovative spirit.

              Iron is the planet's most common element, forming large portions of both the inner and outer core of Earth. Beads dating from 3500 BC found in Egypt contained a relatively large percentage of nickel. The presence of nickel indicates that the iron was of meteoric origin, which was revered because it came from the heavens. Believed to be a blessed metal, this iron was commonly used to create tools use in both religion and war. Weapons made of iron were superior to those made of bronze because of their higher durability and rust resistance.

             Production of iron was not realized until the Middle Bronze Age and it took hundreds of years for the metal to become prominent throughout the world. Early iron production took place in what is now Syria around 2700 BC when the Hittites began to develop mines. The practice of smelting iron spread from there throughout the Middle East, leading to the dawn of the Iron Age around 1300 BC.

Tin

Tin's history dates back to the Bronze Age. This common metal was used to create bronze as early as 3000 BC in the Middle East and Balkans. The earliest known use of tin in Europe was in 2500 BC in the Erzegebirge region, which today lies between Germany and the Czech Republic. Knowledge of mining the metal spread from there around 2000 BC to the British Isles and Iberian Peninsula. Deposits throughout the continent were heavily exploited under the Romans. During the Medieval era, British deposits replaced those of the Iberian Peninsula and Germany as main producers of tin. Other large deposits were later discovered in Sub-Saharan Africa, Central and South America, Southeast Asia and Australia.

Aluminum

Aluminum, another common metal, was used by Greeks and Romans as an agent to set dye onto fabrics and as an astringent for cleaning wounds. The metal is still used today as styptic agent, used to stop bleeding. French chemist Guyton de Morveau called the metal "alumni" when he experimented with it in 1761 and British chemist Humphry Davy first coined the term "aluminum" in 1808.

Author: Srikanth Chaganti

What is an Ore?

Ore   Ore is natural   rock   or   sediment   that contains one or more valuable   minerals , typically containing   metals , that can be mi...