Whilst the commercial value (and also to some extent the relative rarity) of minerals is often rather subjective and incredibly difficult to determine, there are a few slightly less ambiguous “facts” that may be cited with a reasonable degree of certainty.


HIGHEST RECOVERED ROCK (MINERAL) ON EARTH
The summit of Mount Everest (Tibetan name: “Qomolangma”, meaning Holy Mother) is a fossil bearing limestone of the Ordovician Period (485.4-443.8 million years ago). These sedimentary rock deposits comprised of calcium carbonate (and consisting mainly of calcite) are part of a thick pile of sediments of Cambrian to Eocene age which accumulated on the continental shelf of India. They suffered only shallow burial, up to ~10 km (-6 mi) preceding and during continental collision. They are known formally as the Tethyan Sedimentary Sequence. The small chunk of Ordovician limestone in the photograph below was collected only 12 m (40 ft) from the 8,848 m (29,029 ft) top of Mount Everest on 29th May 1953 by Sir Edmund Percival Hillary KG ONZ KBE, when he and Sherpa mountaineer Tenzing Norgay became the first climbers confirmed to have reached the summit of Mount Everest. It was subsequently donated by Hillary in 1953 to the Sedgwick Museum of Earth Sciences (the geology museum of Cambridge University) in England.



DEEPEST RECOVERED MINERAL ON EARTH
In 2018, hidden inside a diamond forged deep within the belly of the Earth, scientists found the first evidence of a mineral that has never been seen before. From South Africa's famous Cullinan Mine, it is a high-pressure perovskite-structured polymorph of calcium silicate that, without the hard casing of the diamond, scientists have never been able to keep stable at the Earth's surface. Scientists estimate that the mineral is the fourth most abundant mineral on Earth, but they have never been able to observe the substance at the surface because as the mineral ascends to the surface less pressure is exerted on it and its carbon bonds are rearranged. Although other versions of calcium silicate perovskite have been found in "medium pressure form" in other diamonds, the new find is the first time it has been seen as it exists hundreds of miles below the Earth's surface. The diamond containing the perovskite was actually found less than a mile beneath the surface, but scientists have determined that it would have originated at a depth of more than 643 km (400 mi). At that depth, it can withstand the pressure of 240,000 Earth atmospheres. The type of diamonds usually seen in jewellery typically are not found more than 160 km (100 mi) below the surface. This particular perovskite and the carbon originally started on the Earth's surface as ocean crust. When it was sub-ducted down in the Earth's mantle it kept going until it was transformed into higher and higher pressure mineral phases.



LARGEST CRYSTALS ON EARTH
The “Cueva de los Cristales” (Cave of the Crystals) is a horseshoe-shaped large cavity in limestone at a depth of 980 ft (300 m) that is connected to the Naica Mine in Chihuahua State, Mexico. The main chamber contains giant selenite (a variety of gypsum) crystals which are some of the largest natural crystals ever found. It has been estimated that some of the more substantial ones would have taken approximately 1 million years to reach their current size. The cave's largest crystal found to date is 12 m (39 ft) in length, 4 m (13 ft) in diameter and 55 tons in weight. When it was accessible, the cave was extremely hot, with air temperatures reaching up to 58 °C (136 °F) with 90 to 99 percent humidity. It remains relatively unexplored due to these factors because without proper protection people can only endure approximately ten minutes of exposure at a time. The cave was discovered in April 2000 by miners excavating a new tunnel for the Industrias Peñoles mining company in Naica. The Naica mining complex itself contains substantial deposits of silver, zinc and lead. Accessibility to the “Giant Crystal Cave” was dependent on the mine water pumps, so once normal mining operations ceased the crystals were visually documented and the caves were then allowed to re-flood in October 2015, to be filled once more with the water rich in minerals required for the crystals to flourish. As the crystals deteriorate in air, and also any further exploration of the cave would have required significant removal of them, the re-flooding has ensured that the crystals remain preserved for now.



HARDEST DISCOVERED NATURAL MINERAL
Whilst diamond is the hardest known natural material on Earth and it is the industry standard for grinding, cutting, drilling and polishing jobs, new types of ultra-hard carbon crystals were found embedded in a Finnish meteorite in 2010 which put the precious stone to shame. The Haverö meteorite, an achondrite (stony) meteorite of the Ureilite group, was seen to fall on 2nd August 1971 on the island of Haverö in Southwest Finland. When researchers subsequently used diamond paste to polish a slice, they noticed something extraordinary: small pockets of material emerging in relief from the surface. The crystals were raised more than 10 µm above the polished surface, which meant they were harder than the diamonds in the polishing paste. The researchers had seen carbon crystals that resisted the diamond polishing in one direction before, but the new crystals were unaffected when polished in every direction. Natural diamond is so hard because the carbon atoms inside it are arranged in a tetrahedron-shaped lattice that is immensely strong. In Haverö, the researchers found crystalline carbon arranged in a rhombohedral lattice. Although this type of diamond was predicted to exist decades ago, and was similar to synthetic man made diamonds, it had never been seen in nature. Unfortunately these new carbon crystals were too small to test for precise hardness, but they are most definitely known to be harder than normal diamonds.



HEAVIEST MATERIAL ON EARTH (AND BEYOND)
Lead is a stable metal that is often used as weights and sinkers. The reason it is heavy in terms of mass per unit volume is because the lead atoms are very close, making it a dense material. However, it is osmium that has the distinction of being probably the heaviest material on Earth, weighing twice as much as lead comparatively. Osmium is a chemical element in the platinum group of metals; it is often used as alloys in electrical contacts and fountain pen nibs. The element's lack of abundance on Earth means it is also incredibly rare. In the Earth's crust, osmium makes up only 50 parts per trillion (ppt). It is estimated to be about 0.6 parts per billion in the universe and is therefore the rarest precious metal.

Beyond Earth, the heaviest, most dense substance in the known universe would have to be the insides of a neutron star. Just a teaspoon-size portion of a neutron star would weigh around a billion tons which, according to NASA, is about the same as Mount Everest! The birth of a neutron star is essentially the collapse of a giant burnt out star, a sun that is 10 to 100 times bigger than our own sun. RX J1856.5−3754 is a nearby neutron star in the constellation Corona Australis. It is the closest neutron star to Earth yet discovered. Thought to have formed in a supernova explosion of its companion star about one million years ago, it was discovered in 1992. Observations in 1996 have confirmed that it is a neutron star and further observations in 2002 indicate that its distance is about 400 light-years from Earth.



OLDEST DISCOVERED FOSSIL
The oldest known fossils, dated to around 3.5 billion years old, are of Cyanobacteria which is found in the Archaean Eon rocks of the Pilbara Craton, Western Australia, Australia. They are among the easiest microfossils to recognise. Morphologies in the group have remained much the same for billions of years, and they may leave chemical fossils behind as well, in the form of breakdown products from pigments. Small fossilised Cyanobacteria have been extracted from Precambrian rock, and studied through the use of SEM and TEM (scanning and transmission electron microscopy). Stromatolite, layered sedimentary structures created by the growth of bacteria or algae. They were originally formed by the growth of layer upon layer of Cyanobacteria, a single-celled photosynthesising microbe. These early life forms have also been tremendously important in shaping the course of evolution and ecological change throughout Earth's history. The oxygen atmosphere that we depend upon was generated by numerous Cyanobacteria photosynthesising during the Archaean and Proterozoic Eon. Before that time, the atmosphere had a very different chemistry, unsuitable for life as we know it today. The name Cyanobacteria comes from the colour of the bacteria (Greek: κυανός, romanised: “kyanós”, literally meaning blue), hence Cyanobacteria is sometimes also called “blue-green algae”.



OLDEST “EARTH ORIGINATED” ROCK (MINERAL)
In February 2014, scientists published their findings in the Journal of Natural Geoscience after analysing single atoms of lead in a zircon crystal from Australia’s Jack Hills range in mid-west Western Australia. The trace elements found in the zircons suggest they came from water-rich, granite-like rocks such as granodiorite or tonalite. Regarded as the oldest material of terrestrial origin found to date, the zircons are from the earliest evolution of the Earth and Moon about 4.533 billion years ago, during the Cryptic Period of the Hadean Eon. Detrital zircons (particles of rock deposited as sedimentary rock derived from pre-existing rock through processes of weathering and erosion) with ages greater than 4 billion years old have been found in these rocks, and a 4,404 +/-8 million year old Zircon was found at Eranondoo Hill; this is the oldest dated material originating on Earth.



OLDEST “EARTH RELATED” ROCK (MINERAL)
Older even than the zircons found on Earth itself is a rock sample from Earths only natural satellite, picked up during the Apollo 16 mission in April 1972. The Moon rock, known simply as Lunar Sample 67215, is an anorthosite (composed predominantly of calcium-rich plagioclase feldspar) believed to be about 4.46 billion years old. Analysis of the rock shows that it comes from a relatively shallow depth in the Moon’s crust, which sheds some light on how the initial lunar crust was formed - this information also provides insight into the formation of the terrestrial planets. Researchers believe that the age of the rock show that the lunar anorthosites formed during the early history of the Moon, most likely by crystallisation from a magma ocean.



OLDEST SOLAR SYSTEM ROCK (MINERAL)
A 1.5 kg CV3 chondrite meteorite, a carbonaceous chondrite (stony) meteorite was found in 2004 in Morocco (and purchased at Erfoud) that is believed to have originated from the asteroid belt between Mars and Jupiter. Analysis of NWA 2364, one of the many Northwest Africa Meteorites, has revealed that the calcium-aluminium-rich inclusions within are from a time before that asteroid belt existed. The most common and characteristic minerals in a Ca–Al-rich inclusion include anorthite, hibonite, melilite, forsterite-rich olivine, perovskite, calcic pyroxene, and aluminous spinel. These minerals may have formed just after part of an interstellar gas and dust cloud, or nebula, had collapsed and formed our Sun. At 4,568.2 million years old, the minerals push back the birth of the Solar System by as much as two million years - and suggests that an exploding star injected key materials into our system as it was being born.



OLDEST DISCOVERED PHYSICAL MATERIAL - SO FAR!
The Murchison meteorite is a carbonaceous chondrite (stony) meteorite of the CM group (type 2) that was seen to fall on 28th September 1969 near Murchison, Victoria, Australia. In January 2020, cosmochemists reported that the oldest material found on Earth to date is the silicon carbide (SiC) particles from the Murchison meteorite. This ancient interstellar dust, made of presolar grains (dust grains that predate our Sun), was belched into the universe by dying stars during the final stages of their lives. Some of that dust eventually hitched a ride to Earth on an asteroid that produced the Murchison meteorite. Presolar grains were known to be older than the Sun but had not been precisely dated. Although the universe abounds with floating stardust, no presolar grains have ever been found in Earth's rocks. That is because plate tectonics, volcanism and other planetary processes heated and transformed all the presolar dust that may have collected during Earth's formation 4.54 ± 0.05 billion years ago. However, some primitive meteorites do contain these presolar grains, the solid particles that formed in the interstellar medium before being incorporated into the Solar System. Scientists have examined neon isotopes in the presolar silicon carbide grains extracted from the Murchison meteorite which allowed them to calculate how long each grain had remained in the interstellar medium, a period of time ranging from 3.9 ± 1.6 million years up to 3 ± 2 billion years before the formation of the Solar System, making the grains the oldest known solid material. Although some grains were even older than 5.5 billion years most of them had presolar ages of less than 300 million years, constraining astronomers' models of how long dust survives in the interstellar medium.




MOST USEFUL “MINERAL” ON EARTH?
This is probably open to much debate, but copper is arguably one of the most vital elements to modern life. Copper is one of the few metals that can occur in nature in a directly usable metallic form, as well as in a variety of minerals. Evidence suggests that gold and meteoric iron (but not smelted iron) were the only metals used by humans before copper. The history of copper use dates to around 9000 BC in the Middle East. Copper smelting was independently invented in different places, but it was probably discovered in China before 2800 BC. Experience with copper assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC. The earliest copper alloy weaponry dates back to this period too. Ancient Egyptians used copper to disinfect wounds and surgical tools. For thousands of years, copper has been so widespread that most people encounter it without even noticing. From building tools to biology, copper is an essential part of human life. We even need 1.2 milligrams of copper daily to help enzymes transfer energy inside our cells. As the Egyptians documented, copper is known to kill many germs on contact. Modern research has found that MRSA (a bacterium responsible for difficult-to-treat infections in humans) cannot survive on copper surfaces the way it can on the platinum metals often used in hospital building railings, doorknobs, and beds. Thanks to its antimicrobial properties and its ability to fight bacteria, hospitals are installing copper touch surfaces around the world to halt the spread of bacterial infections in hospital settings. Copper is used everywhere for electric cables and wires, for switches in households, industry, machinery, transport. It is used extensively for plumbing, heating, electrical and roofing materials, various other electric components, consumer and general products, as well as in jewellery. The versatile metal can treat conditions like arthritis, cancer and heart disease, whilst also helping to make local economies run with copper-based coins. For thousands of years, copper has played a rather pivotal role in powering our daily lives and making the modern world work. Here are a few ore minerals of copper (with the approximate percentage of copper they typically contain), but there are others too.

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The content of this article has been researched from a variety of online & literary sources with accordant corroboration.