Facts about gold

The element gold is a pirate’s booty and an ingredient in microcircuits. It’s been used to make jewelry since at least 4000 B.C. and to treat cancer only in recent decades. It’s in the pot at the end of the rainbow and in the coating on astronaut visors. Gold is an element that bridges old and new — and myth and science — seamlessly.

Gold, the 79th element on the Periodic Table of the Elements, is one of the more recognizable of the bunch. It is malleable and shiny, making it a good metalworking material. Chemically speaking, gold is a transition metal. Transition metals are unique, because they can bond with other elements using not just their outermost shell of electrons (the negatively charged particles that whirl around the nucleus of an atom), but also the outermost two shells. This happens because the large number of electrons in transition metals interferes with the usual orderly sorting of electrons into shells around the nucleus.

Gold represents a tiny fraction of the elements in the known universe. The reason for its rarity is owed to the incomprehensible amount of energy needed for its formation. Gold is formed in stars, but only in those that are exploding in giant supernovas, or incredibly dense ones that have come together in monstrously powerful collisions, according to the journal PNAS . 

Stars, such as our sun, generate energy through the power of fusion, where smaller elements are fused, or combined, together into heavier elements. To start with, a star may be mostly hydrogen, the smallest element. The process of fusion under immense pressure and heat in the star’s core will generate helium. When hydrogen runs low and the star begins to reach the next phase of its life cycle, it will fuse helium into the next heavier element, and so on. 

This process continues until the element of iron, where the balance suddenly shifts. Because fusing iron does not create energy, it consumes it, according to the University of Oregon. With no means of generating internal energy to counteract its own immense pressure and gravity, the star begins to collapse onto itself. If the star is large enough the result is a supernova — a massive star explosion, according to NASA. Heavier elements are formed during the incredible energy generated during this process, including gold. 

From Eastern Europe to the Middle East to the tombs of Egyptian Pharaohs, gold appears throughout the ancient world. Five thousand years ago, the massive Nile River was the key to the ancient Egyptian empire, according to the Australian government. Its water allowed a bounty of crops to be grown along its edge, keeping its citizens, and its armies, well fed. But there was also a shiny yellow metal that came running down the river, the element of gold. The Egyptians eagerly took this visually appealing treasure and found that because it was naturally pure and malleable, it required little refinement to be turned into mesmerizing decorations. 

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