The name is thought to derive from the Greek "Topazios," but the stone mined on the Red Sea island that inspired the name was actually peridot. For millennia, every yellow stone was called topaz. The confusion of names is, in itself, the history of this stone.
In 1740, a 1,680-carat stone found in Brazil was believed to be diamond and set into the Portuguese crown. Later identified as topaz, it was never removed. It remains known as the "Braganza Diamond."
An aluminium silicate containing fluorine, Mohs hardness 8. A traveller's talisman in ancient Rome, the stone of the sun god Ra in Egypt. The human habit of finding meaning in yellow stone predates mineralogy by a considerable margin.