Aquamarine is a pale blue-green gemstone that gets its name from Latin words meaning “water of the sea.” Look at pictures of tropical ocean water on a sunny day, where the shallow water glows with that beautiful blue-green color. That's the color of aquamarine. The stone is actually a variety of the mineral beryl, the same family that includes emeralds.

Aquamarine has been prized for thousands of years. Ancient sailors believed carrying aquamarine would protect them during ocean voyages and calm rough seas. Today, jewelers cut aquamarine into rings, necklaces, and earrings. The largest aquamarine ever found weighed over 240 pounds and was discovered in Brazil in 1910.

The word aquamarine can also describe that same distinctive color, somewhere between blue and green. You might describe someone's eyes as aquamarine, or paint a bedroom wall aquamarine if you want it to feel calm and oceanic. Unlike words like “blue” or “green,” calling something aquamarine suggests that particular crystalline, water-like quality that makes the gemstone so appealing.