Vibrant as the gemstone, not the Australian town, nor just any green.
Emerald is a vivid green.
It can be described as vivid, vibrant, strong and bold.
Set in black, because black reads best on it.
Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium or sometimes vanadium. Beryl has a hardness of 7.5–8 on the Mohs scale. Most emeralds have many inclusions, so their toughness is classified as poor. Emerald is a cyclosilicate. It occurs mainly in association with quartz, muscovite, albite, mica schist, Pyrite schorl, microcline, fluorite, smoky quartz and elbaite.
Read on WikipediaVarieties of the color green may differ in hue, chroma or lightness, or in two or three of these qualities. Variations in value are also called tints and shades, a tint being a green or other hue mixed with white, a shade being mixed with black. A large selection of these various colors is shown below.
Read on WikipediaProper noun