Metamorphic Rock Companion – Tanzanite
Tanzanite was discovered in 1967 in northern Tanzania and was initially mistaken for sapphire before being recognized as a new gem. Gem-quality blue tanzanite was promoted by Tiffany & Co., with deep blue and indigo hues being the most prized. Tanzanite exhibits strong pleochroism, meaning its color can vary depending on the cutting direction. In Taiwan, tanzanite entered the market around 1995, initially as a substitute for sapphire due to its similar color. Thanks to Tiffany’s efforts, tanzanite has since gained recognition as a unique and rare blue gemstone, with prices around NT$10,000 to NT$15,000 per carat.