December celebrates four stunning birthstones in shades of blue: tanzanite, turquoise, blue topaz, and zircon. Tanzanite, discovered near Mount Kilimanjaro in 1967, is found in only one place on Earth, making it rarer than diamonds. This remarkable gem displays different colors when viewed from different angles—a property called pleochroism. Turquoise, treasured for over 7,000 years, has been sacred to cultures from ancient Egypt to Native American tribes, with its distinctive robin's egg blue and matrix patterns. London blue topaz offers a sophisticated, deep steel-blue hue that rivals fine sapphire, combining exceptional brilliance with accessible luxury. Zircon, one of Earth's oldest minerals, dazzles with exceptional fire and brilliance that rivals diamond. Often found in brilliant blues, zircon has been prized since ancient times and should not be confused with synthetic cubic zirconia. Our December birthstone collection celebrates these four blues, from tanzanite's violet-tinged rarity to turquoise's ancient legacy, London blue topaz's contemporary elegance, and zircon's timeless sparkle.