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 gemstones, are graded using four basic parameters–the four "C"s of connoisseurship: "color", "clarity," "cut" and "carat weight". Normally, in the
Hooker Emerald Brooch Emerald at the centre of the brooch. Ten pairs of baguette-cut diamonds project between the spokes from behind the emerald towards the platinum band. The Hooker Emerald itself weighs . It measures to a side and is remarkably free of inclusions for its size. The gem's cut gives the appearance of a series of concentric squares within the gemstone (known as a beveled square emerald cut.) In total, the brooch contains approximately of diamonds. The Hooker Emerald was extracted from an unidentified mine in Colombia in the 16th or 17th century. The rough emerald was sent to Europe by Spanish