In the ancient world, zircon was called hyacinth - and some still call it by that name today. The colors listed for Hyacinth include yellow, orange, and red. So if someone is trying to sell or show you a hyacinth stone at a gem show, now you'll know that it's a zircon.
In addition to being a versatile gemstone, zircon also has some really neat geological properties. Because zircon likes to hold on to trace amounts of uranium, and because uranium decays at a known rate when exposed to lead, geologists use zircon crystals to date rocks by finding the age of the zircon within specific specimen! Scientists have found this method to be even more accurate than radiometric, or carbon, dating methods. In fact, using this method, scientists discovered that the Jack Hills in Western Australia, which supplies about 37% of the zircon on the market, are among the oldest minerals on earth and date at nearly 4.4 billion years old!