Aquamarine is the pale blue to light green kind of beryl, a beryllium aluminium silicate, its sea colour coming from small amounts of iron held in the crystal. It grows as six-sided prisms, from tiny to huge, mostly in granite pegmatites and in veins laid down by hot mineral-rich water. Because it is fairly plentiful it costs less than emerald, its green relative. The name joins the Latin for water and for the sea. Wikipedia records that it is the birthstone for March, that the ancient Greeks cut it into engraved gems, and that an old tale of mermaids led sailors to carry it as a lucky charm against shipwreck; the largest cut stone, the Dom Pedro, came from Minas Gerais in Brazil. Cunningham gives it to the Moon and to water, calls it the stone of the old sea goddesses, and notes aquamarine beads found in Egyptian burials. He uses it to bring psychic impulses through, to purify the body before ritual, to bring peace and happiness between partners, and as a guard for anyone travelling over water. Hall calls it a stone of courage whose calming energy quiets the mind, says sailors once carried it against drowning, and links it with clearer communication, sharper intuition and meditation.