Tanzanite

Tanzanite is one of the rarest gemstones in the world. It's the blue and violet variety of the mineral Zoisite, ranging from blue to bluish-purple to bluish-violet depending on viewing angle, and it's found in only one place on earth: a small area in northern Tanzania near Mount Kilimanjaro. The name "Tanzanite" was actually coined by Tiffany & Company when they introduced the stone to the world in the 1960s — they could have called it "blue Zoisite" but thought Tanzanite had a better ring to it. It's become the second most popular blue gem in the world after Sapphire. It's important to note that heating is extremely common in the Tanzanite trade — most Tanzanite on the market has been heated to enhance the blue-violet color.