Topaz is an aluminium silicate that contains fluorine and hydroxyl. In its pure form it is colourless (white). Impurities are what cause variations in colour. Topaz has a history that goes back at least two thousand years. The use of topaz goes back to Egyptian times when the ancient Egyptians believed that yellow topaz received its golden hue from the Sun God, Ra. Some believe that "topaz" is a Middle English word, which was acquired from the Old French word "Topace" and Latin "Topazus", the root of which is in the Greek word "Topazios" or "Topazion"; the ancient name of an island in The Red Sea where the ancient Greeks mined a yellow gem that they believed to be topaz. The name of the island means "to seek" in Greek. It could have been so named because it was difficult to find amongst the mist. This island is now known as "Zabargad" or "St John's Island", and it is thought that the gem mined by the ancient Greeks was actually "chrysolite". The Christian Old Testament makes references to topaz, but this gemstone may have also been "chrysolite", rather than topaz. The word "topaz" could also have stemmed from the Sanskrit (the ancient language of India) word, "tapas", which means "fire".
Deposits of topaz have been found in Brazil, Afghanistan, Australia, Myanmar (Burma), China, Germany, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia, Zimbabwe, Sri Lanka, Ukraine and the USA. Natural light-blue topaz is found in Northern Ireland and the UK. Enormous topaz crystals have been discovered in Minas Gerais (Brazil) and Ukraine.