A century ago crude oil was the most valuable substance on the planet, but the coronavirus pandemic has caused the price per barrel to plummet. But how have the likes of diamonds, gold, and platinum fared? Plus there are a host of other obscure materials you’ve probably never heard of that command a high price for the fact they’re ultra-rare, hard to extract or valued for highly unique properties. Click or scroll through to discover the most valuable substances on Earth, as of their prices at the time of writing (22 March).

It might seem odd that raw fish eggs are among the most illustrious and expensive substances in the world, but gourmands will tell you there's no better taste. Iranian beluga caviar is the most costly caviar in the world at a reported price of $80 per ounce, which works out to $2.66 per gram. The beluga, the fish from which this rare caviar is produced, typically takes 10 years to begin producing eggs, and the fish is extremely rare at the moment due to overfishing.

Crème de la Mer is an anti-aging ‘miracle’ cream that currently costs $190 for a one ounce tub, which works out at $6.33 per gram. Known for reducing wrinkles, Crème de la Mer is the most famous moisturizer in the world and is currently owned by the cosmetic giant Estée Lauder. Some of its age-defying ingredients include seaweed, natural sea and plant oils, lime extract, and wax-like thinning agents.

Another one of the most expensive garnishes in the world is the wonderfully aromatic saffron. This sultry spice is a flowering plant that is used in a variety of ways. Saffron is used as a coloring agent, for seasoning, to scent rice, and also as a natural remedy to combat everything from depression to menstrual cycles. Its subtle taste and medicinal properties make saffron one of the most sought-after substances on the planet, costing up to $2,200 per pound for premium quality saffron, or $6.99 per gram, according to wholesaler Golden Saffron.

Truffles of any variety are a notoriously expensive foodstuff, but the ultra-rare Italian white truffles top the charts. According to Truffle.farm’s truffle price tracker, these truffles sell for an astonishing $214.26 per ounce, which works out at around $7.14 per gram.

To'ak chocolate is the most expensive chocolate in the world and is made by a company in Ecuador, which uses barrel-aging similar to the procedure used by whisky-makers. A 50-gram bar of the best To'ak chocolate can cost as much as $450, which works out as $9 per gram. You will find a rare heirloom Nacional cacao bean, which has been DNA tested, in the center of the bar. The ultra-expensive sweet treat contains 77% pure cacao from Ecuador, which has been matured for three years.

Platinum is a metal that is highly sought-after for jewelry, but it has a multitude of other uses too. Platinum can be used in scientific experiments and is also used in anti-cancer drugs. The metal is actually so rare that all of the platinum ever mined fits into an average-sized living room, making it rarer than gold. Many precious metals have lost value as a result of the coronavirus pandemic, however, as uncertain markets have caused investors to trade in investments for hard cash. As the coronavirus pandemic hit last year, between February and March 2020 platinum prices plunged by 40% according to Reuters, but a year on the price of platinum has bounced back and now sits at $38.20 per gram according to monex.com.

Although revered by everyone from ancient Aztec tribes to chart-topping hip-hop MCs, gold is much more than a shiny metal that exudes an image of wealth. Gold can be used in electrical conductivity or even eaten in the form of gold leaf, and it remains one of the most expensive substances on Earth. In times of crisis such as the coronavirus pandemic, analysts are quick to see what will happen to the price of the precious metal, but while the price of gold was initially boosted last year, peaking at $70 on 7 August, it then started to drop off. In fact, it has lost more than 20% in value since those highs. Currently gold is priced at $55.78 per gram, according to Bullion By Post, a drop of 2.72% on the price this time last year. It is expected that once vaccine drives are over the price of gold will rise once again when economic activities return to normal.

This silvery-white metal is one of the rarest metals in the world and is normally in high demand as it is a key component in catalytic converters, which are found in car exhausts. More than 80% of palladium is used in this way, but the metal is also used in jewelry, where it is sometimes referred to as ‘white gold’. Over the past year palladium has been outperforming gold, and its current price is $2,604 per ounce or $83.72 per gram as of 22 March. Analysts predict the price could go up even higher in 2021 due to supply issues; for example, the world's largest palladium producer, Nornickel, has seen mine closures due to water issues.

Iridium is a by-product of nickel and copper production and is a dense, silvery-white metal. It’s the most corrosion-resistant metal on the planet and is routinely used as a hardening agent for platinum alloys. You will find it used in pen tips, compass bearings and for making crucibles in very hot temperatures. The reason it’s so expensive, at $192.93 per gram, is that it’s one of the rarest elements found in the earth’s crust.

Another rare and valuable precious metal is rhodium, which is currently the most expensive metal in the world. Similar to palladium, this silvery-white and hard corrosion-resistant metal is mainly used in the manufacturing of catalytic converters (pictured) in cars. However, rhodium has qualities that make it even more desirable to car manufacturers as the metal is better at removing nitrous oxides from vehicle fumes, and is easier to install in existing converters. The demand for rhodium by the automotive industry initially dropped as a result of the pandemic, and so did its value. But it's since bounced back and now commands a price of $28,600 per ounce, meaning that a gram of rhodium would set you back $919.51.

It’s inconceivable that a cup of tea could cost hundreds of dollars, but this is not just your average cup of English Breakfast or Earl Grey. Da Hong Pao tea, sourced from Fujian Province in China, costs 25 times more than gold at an average of $1,400 per gram. Sometimes It can cost even more than that; in 2002, a collector purchased just 20 grams of Da Hong for a shocking $28,000. That’s a serious pot of cash for a pot of tea!

You might be surprised that several types of venom can fetch a small fortune. One of the priciest is coral snake venom, which is favored for its antiviral and antibacterial properties, and is priced at an astonishing $4,000 per gram. Coral snakes have the second strongest venom of any snake, after the black mamba, and are recognizable for their vibrant colors.

If you are thinking of building a nuclear reactor or weapons of mass destruction, plutonium is the key ingredient that you can’t do without. At approximately $4,000 per gram, it really is an expensive substance. This radioactive chemical is only found today in trace amounts of uranium, which makes it a rare and sought-after substance, especially for tyrannical dictators.

Taaffeite gems are a million times rarer than diamonds and can cost around $2,500 per carat (0.2 grams), which works out as $12,500 per gram. Although they can be immensely difficult to find, they are usually found in ultra-expensive jewelry.

With the rarest varieties costing approximately $4,253 per carat, according to gem price appraisal site Gemval, the Benitoite blue gemstone is one of the rarest substances known to humans. Formed in the late cooling stages of a hydrothermally-altered serpentinite, Benitoites are found in San Benito County in California and are some of the most striking and glittery gems on the planet.

You may never have heard of it, but Soliris is a highly valuable drug used to treat an ultra-rare disease called Atypical Haemolytic Uraemic Syndrome (aHUS). It’s also one of the most expensive drugs in the world, costing a jaw-dropping $6,820 for a 300mg vial, which equates to $22,733 per gram.

Tritium is a form of hydrogen or an isotope that is radioactive in nature that can be produced naturally in the upper atmosphere from the coming together of gases and cosmic rays. When you see the self-illuminating ‘EXIT’ signs in public buildings, it’s the tritium that creates the luminescent glow. It’s highly unlikely that you will ever need tritium, but if you do a gram is more expensive than a family car, at $30,000.

Red beryl is one of the world’s rarest gemstones. To give you an idea of how rare it is, one red beryl crystal is found for every 150,000 gem-quality diamonds. One carat of red beryl can cost up to $10,000 for top specimens, according to gem company GemSelect, with the precious stone costing $50,000 per gram. The stone can only be found in tiny quantities at three sites in the world in Utah and New Mexico.

When it comes to rare and expensive gemstones, not many can match the exquisite and unique Serendibite inosilicate mineral. Initially discovered in Sri Lanka in 1902, and more recently in Myanmar, this rare mineral can cost in the region of $18,000 per carat (0.2 grams). With a complex chemical make-up, this much sought-after inosilicate is mainly used in ultra-expensive jewelry.

According to jewelry industry magazine National Jeweller, a grandidierite gem on display at Willensky Gallery in New York, weighing 4.96 carats (almost one gram), was priced at $129,500 in 2019. The rare gemstone was discovered in 1902 in Madagascar. Clear and facet grade Grandidierite stones are some of the hardest gems to find.

Diamonds are said to be a girl’s best friend. But they're the bank manager’s too. Although the price of a diamond heavily depends on its quality and the cut, a pure one-carat diamond can cost up to $26,950 per carat (0.2 grams), which roughly equates to $134,750 per gram. Although we believe that the massive price tag is because of the scarcity of diamonds, the truth is that all diamonds are not so rare. But the rarer ones are expensive.

Painite is one of the rarest borate minerals in the world and was first discovered and named after British mineralogist Arthur C D Pain, who originally thought they were sapphires. The mineral comes from Myanmar and there are believed to be approximately 1,000 painite crystals in circulation. Because they are so rare, a single carat (0.2 grams) of Painite can cost $60,000 and it's mainly used for ultra-lavish engagement rings.

Although we have already mentioned diamonds, it is important to point out that red diamonds are the rarest stones on the planet and can cost in the region of $1 million per carat (0.2 grams). There are fewer than 30 red diamonds known to humans, most of which weigh less than half a carat. The largest red diamond ever found was 5.11 carats and was sold for $8 million in 2011.

You might have heard the term ‘designer drugs’, but ‘designer chemicals’ are also a massive business. Californium 252 is a special isotope that is used to find the layers of water and oil in oil wells. This synthetic radioactive element has a half-life of 2.645 years and is produced by nuclear reactors. The chemical was first made in 1950 at Berkeley in California and can cost a jaw-dropping $27 million per gram.

When it comes to finding the most expensive substance known to humans, nothing else comes close to antimatter. If you thought this substance only existed in science fiction, think again. NASA scientists back in 1999 said it would cost $62 trillion to make a gram of antihydrogen, but in this day and age the price is closer to $23.6 billion per gram. It is believed that in years to come that this special substance will fuel intergalactic space travel, but for now that does remain in the realms of science fiction. 

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