Emerald the Meenakshi Amman Temple in Madurai, is the goddess Meenakshi, whose idol is traditionally thought to be made of emerald. Emerald Emerald is a gemstone and a variety of the mineral beryl (BeAl(SiO)) colored green by trace amounts of chromium and sometimes vanadium. Beryl has a hardness of 7.5–8 on the Mohs scale. Most emeralds are highly included, so their toughness (resistance to breakage) is classified as generally poor. Emerald is a cyclosilicate. The word "emerald" is derived (via and ), from Vulgar Latin: "esmaralda"/"esmaraldus", a variant of Latin "smaragdus", which originated in (smaragdos; "green gem"). Emeralds, like all colored
USS Aquamarine (PYc-7) named for the gemstone aquamarine. Assigned to the Naval Research Laboratory, Bellevue, D.C., "Aquamarine" assisted in experimental work, chiefly underwater sound. Although most of her experiments were conducted on the Potomac River and Chesapeake Bay, she also operated off New London, Connecticut, from 16 October to 4 November 1943, and off the Florida coast and in the Bahamas from 24 January 1944 to 18 April 1945. During 1945 and 1946 "Aquamarine" had additional duty as special tender to the presidential yachts and . "Aquamarine" was decommissioned on 21 June 1946 and transferred to the Maritime Commission on 31 January 1947