Covering objects with a thin layer of gold is an ancient technique.
If you can't afford a solid gold ring, you can opt for a gilded or gold-plated one, thanks to Italian chemist, Luigi Brugnatelli's invention of modern electroplating in 1805.
Even before his discovery, the act of coating ordinary metal objects with gold and silver had been in practice.
Some kings would have gilded crowns; aristocrats would order for picture frames, statues, tombs and ceilings to be coated with gold leaves.
Gilded statues and ceilings could be found in temples and public building as well.
Over those years, several gilding techniques were used. For example, when gilding an iron crown, smiths would hammer a thin layer of gold, lay it over the crown and then bake the two into one piece.
Other objects that could not be heated like wooden picture frames and ceilings were treated differently.
Artists would hammer gold into very fine sheets called gold leaves, and then cut and glued them in place on the objects.
Archaeologists have found gilded and gold leaf artworks dating back to 1,500BC in Greece, Egypt and China.
As these works from the Minoan, Egyptian and Shang dynasties are very sophisticated, many believe that the techniques used in their production are much older - exactly how old, though, remains a mystery.
Facts;
- By weighing his king's crown in water, ancient Greek mathematician Archimedes could work out whether it was solid gold or gilded.
- One of seven wonders of the ancient world was a 12m high gilded statue of the Greek god Zeus at a temple in Olympia.
- Alessandro Volta was a professor of physics at the University of Pavia in Italy.
- Gold plating is used in electronics to create corrosion-resistant connectors and circuit boards.