Iolite is the deep blue gem variety of the silicate mineral cordierite, named for French geologist Pierre Cordier. Iolite is found on Garnet Island in Canada and in South Asia and South Africa. Leif Eriksson and other Viking explorers are said to have used thin slices of iolite to navigate during voyages, taking advantage of its prismatic properties to polarize sunlight.

Larimar is a rare gemstone found only in an inaccessible region of the Dominican Republic overlooking the Caribbean Sea. The sky blue stone's name was coined by a Dominican, Miguel Méndez, who combined his daughter's name Larissa, with mar, the Spanish word for sea.