The most expensive things in the world: a painting, a diamond, a stamp and antimatter

Some things are so rare, beautiful or hard to make that their prices are hard to believe. Here are the most expensive things in the world — from art, jewels, stamps and coins to the things of science that cost crores just to make. Read the car records separately in The world's most expensive car.

The most expensive things sold at auction

"Salvator Mundi" is the most expensive work of art ever sold at auction. Experts still debate how much of it Leonardo painted himself. In the world of stamps, the British Guiana "One-Cent Magenta" is unique — only one copy survives.

The most expensive things in science

• Antimatter: according to an old NASA estimate, making one gram of antihydrogen would cost trillions of dollars. So far only tiny amounts of antimatter have ever been made — it is considered the most expensive substance in the world.
• Californium-252: this artificial radioactive element is made in very small amounts in nuclear reactors. A gram of it is valued at millions of dollars.
• The International Space Station (ISS): several countries built it together. It is estimated to have cost more than $150 billion — considered the most expensive object ever built by humans.

Did you know? The world's most famous diamond, the "Koh-i-Noor", came from the Golconda mines in India. Today it is among Britain's Crown Jewels and has never been sold, so it has no set price — it is called "priceless".

The most expensive everyday things

• Saffron: the most expensive spice in the world. Lakhs of flower threads must be picked by hand for one kilo. Kashmiri saffron is famous worldwide.
• Agarwood (oud): this fragrant wood, formed when a tree is infected by a fungus, is among the world's most expensive woods and perfumes — read more in The world's most expensive wood.
• White truffle: this fungus, which grows underground in Italy, is so rare that dogs are used to find it, and its price can reach lakhs of rupees a kilo.

The most expensive homes

Mumbai's "Antilia" is counted among the most expensive private homes in the world — the 27-storey building is the home of the industrialist Mukesh Ambani. London's Buckingham Palace and many royal palaces around the world are considered even more valuable, but they have never been for sale, so they have no market price.

Why are things so expensive?

A thing's price is set by three things — how rare it is, how much work or technology it takes to make, and how much feeling or history people attach to it. A painting's canvas and paints are cheap, but because of its artist and its history it can be worth billions of rupees.

Read more: Did you know? 25 amazing facts · Interesting facts.