Zircon is the oldest known mineral on earth, some mineral specimens dating back to over four billion years old! Zircon comes in a wide variety of colors, some heated to create or accentuate a desired color and some colors are naturally occurring, with no heat treatment whatsoever. It is one of the heaviest of the gemstones, but it makes up for its smaller stone size per carat weight by displaying a highly refractive, brilliant, intense fire coupled with a strong dispersion. The wide range of colors, rarity, beautiful aesthetics and low relative cost makes zircon a popular gemstone for jewelry lovers and gemstone collectors alike. Blue Zircon, one of the most popular colors, is also an alternative birthstone for December.