What are The Most Expensive Minerals in The World?

In the mining world, a lot of precious gems have been exploited. Thre value depends on many characteristics that only experts evaluate. In this article, you learn what are those so expensive gems that come deep from mother earth´s crust.

“Black opals are the rarest form of all precious opals and are characterized by their dark body tone and rich colors or ‘fire’. Almost all of the world’s black opals are mined in Australia (which also is the world’s largest overall producer of opals, at 90 percent).

Value: Up to AUD $20,000/US $15,700 per carat

Painite is a red-colored, hexagonal-shaped gem, thought to be the rarest on the planet. It was named after the British gemologist Arthur CD Pain, who discovered it in Myanmar in 1950. It has only ever been found in that region, making it incredibly hard to locate.

Value: US $50,000-$60,000 per carat

Rhodium is a rare, silvery-white element that is corrosion resistant. It also one of the rarest elements on earth and is used in catalytic converters, glass production, and to plate sterling silver jewelry. It is principally sourced in South Africa, the Ural Mountains, and North America.

Value: US $1,360 per troy ounce (1 troy ounce = 1.097 ounce)

Undoubtedly one of the most popular minerals in the world, gold has long been treasured throughout history. It is not the world’s most expensive mineral, but its enduring appeal means it is considered a ‘safe haven’ investment, as well as an object of beauty. Yellow gold is the most popular, although it comes in a range of other hues, including white gold and rose gold.

Value: US $1,292 per troy ounce” https://www.miningpeople.com.au/news/the-10-most-expensive-minerals-in-the-world

 

 

What is an Alexandrite Gemstone?

” Alexandrite, a strongly pleochroic (trichroic) gem, will exhibit emerald green, red and orange-yellow colors depending on viewing direction in partially polarised light. However, its most distinctive property is that it also changes color in artificial (tungsten/halogen) light compared to daylight. The color change from red to green is due to strong absorption of light in a narrow yellow portion of the spectrum, while allowing large bands of more blue-green and red wavelengths to be transmitted. Which of these prevails to give the perceived hue depends on the spectral balance of the illumination. Fine-quality alexandrite has a green to bluish-green color in daylight (relatively blue illumination of high color temperature), changing to a red to purplish-red color in incandescent light (relatively yellow illumination). However, fine-color material is extremely rare. Less-desirable stones may have daylight colors of yellowish-green and incandescent colors of brownish red.

Cymophane is popularly known as “cat’s eye”. This variety exhibits pleasing chatoyancy or opalescence that reminds one of the eye of a cat. When cut to produce a cabochon, the mineral forms a light-green specimen with a silky band of light extending across the surface of the stone.” https://en.wikipedia.org/wiki/Chrysoberyl

What is an Opal?

” Opal is a hydrated amorphous form of silica (SiO2·nH2O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Because of its amorphous character, it is classed as a mineraloid, unlike crystalline forms of silica, which are classed as minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt. Opal is the national gemstone of Australia.

The internal structure of precious opal makes it diffract light. Depending on the conditions in which it formed, it can take on many colors. Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the black opals are the rarest, whereas white and greens are the most common. Opals vary in optical density from opaque to semitransparent.

Precious opal shows a variable interplay of internal colors, and though it is a mineraloid, it has an internal structure. At microscopic scales, precious opal is composed of silica spheres some 150 to 300 nm in diameter in a hexagonal or cubic close-packed lattice. It was shown by J. V. Sanders in the mid-1960s  that these ordered silica spheres produce the internal colors by causing the interference and diffraction of light passing through the microstructure of the opal. The regularity of the sizes and the packing of these spheres determines the quality of precious opal. Where the distance between the regularly packed planes of spheres is around half the wavelength of a component of visible light, the light of that wavelength may be subject to diffraction from the grating created by the stacked planes. The colors that are observed are determined by the spacing between the planes and the orientation of planes with respect to the incident light. The process can be described by Bragg’s law of diffraction.” https://en.wikipedia.org/wiki/Opal

What is a Moonstone?

” Moonstone is a sodium potassium aluminum silicate, with the chemical formula (Na, K)AlSi3O8. Moonstone has been used in jewelry for millennia, including ancient civilizations. The Romans admired moonstone, as they believed it was born from solidified rays of the moon. Both the Romans and Greeks associated Moonstone with their lunar deities. In more recent history, the moonstone became popular during the Art Nouveau period; French goldsmith René Lalique and many others created a large quantity of jewelry using this stone.” https://en.wikipedia.org/wiki/Moonstone_(gemstone)

What is an Aquamarine Gemstone?

” Aquamarine (from Latin: aqua marina, being, water: sea, i.e. sea water, marīna, from marīnus; of the sea.) is a blue or cyan variety of beryl. It occurs at most localities which yield ordinary beryl. The gem-gravel placer deposits of Sri Lanka contain aquamarine. Clear yellow beryl, such as that occurring in Brazil, is sometimes called aquamarine chrysolite. The deep blue version of aquamarine is called maxixe. Maxixe is commonly found in the country of Madagascar. Its color fades to white when exposed to sunlight or is subjected to heat treatment, though the color returns with irradiation.

The pale blue color of aquamarine is attributed to Fe2+. Fe3+ ions produce golden-yellow color, and when both Fe2+ and Fe3+ are present, the color is a darker blue as in Maxixe. Decoloration of maxixe by light or heat thus may be due to the charge transfer between Fe3+and Fe2+. Dark-blue maxixe color can be produced in green, pink or yellow beryl by irradiating it with high-energy particles (gamma rays, neutrons or even X-rays). 

In the United States, aquamarines can be found at the summit of Mt. Antero in the Sawatch Range in central Colorado. In Wyoming, aquamarine has been discovered in the Big Horn Mountains, near Powder River Pass. Another location within the United States is the Sawtooth Range near Stanley, Idaho, although the minerals are within a wilderness area which prevents collecting. In Brazil, there are mines in the states of Minas Gerais, Espírito Santo, and Bahia, and minorly in Rio Grande do Norte. The mines of Colombia, Zambia, Madagascar, Malawi, Tanzania, and Kenya also produce aquamarine.

The largest aquamarine of gemstone quality ever mined was found in Marambaia, Minas Gerais, Brazil, in 1910. It weighed over 110 kg (240 lb), and its dimensions were 48.5 cm (19 in) long and 42 cm (17 in) in diameter. The largest cut aquamarine gem is the Dom Pedro aquamarine, now housed in the Smithsonian Institution’s National Museum of Natural History.”  https://en.wikipedia.org/wiki/Beryl#Aquamarine_and_maxixe

What is a Sapphire?

” Sapphire is a gemstone, a variety of the mineral corundum, an aluminum oxide (α-Al2O3). It is typically blue in color, but natural “fancy” sapphires also occur in yellow, purple, orange, and green colors; “party sapphires” show two or more colors. The only color which sapphire cannot be is red – as red-colored corundum is called ruby, another corundum variety. Pink colored corundum may be either classified as ruby or sapphire depending on locale. This variety in color is due to trace amounts of elements such as iron, titanium, chromium, copper, or magnesium.

Commonly, natural sapphires are cut and polished into gemstones and worn in jewelry. They also may be created synthetically in laboratories for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of very special-purpose solid-state electronics (especially integrated circuits and GaN-based LEDs).

Sapphire is the birthstone for September and the gem of the 45th anniversary. A sapphire jubilee occurs after 65 years.” https://en.wikipedia.org/wiki/Sapphire

How are Diamonds Formed?

“Diamonds are formed at high temperature and pressure at depths of 140 to 190 kilometers (87 to 118 mi) in the Earth’s mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years (25% to 75% of the age of the Earth). Diamonds are brought close to the Earth’s surface through deep volcanic eruptions by a magma, which cools into igneous rocks known as kimberlites and lamproites. Diamonds can also be produced synthetically in an HPHT method which approximately simulates the conditions in the Earth’s mantle. An alternative and completely different growth technique is chemical vapor deposition (CVD). Several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have been developed to distinguish natural diamonds, synthetic diamonds, and diamond simulants. The word is from the ancient Greek ἀδάμας – adámas“unbreakable”.” https://en.wikipedia.org/wiki/Diamond