One word, from a web list
The odd spelling, with no space, gives away where this name comes from. Emeraldgreen is an entry in a long list of over 500 named colors on the Cloford web color table, next to names like cobaltgreen and sapgreen. That list gives it as RGB 0, 201, 87. The page warns that these names don't work in HTML or CSS, so you have to use the code.
It has nothing to do with the old poison pigment called emerald green. That was a copper and arsenic paint, covered on our emerald page. Emeraldgreen is brighter and stronger than emerald, a little bluer than malachite, and darker than spring green. Black text works best on it, at 9.49 to 1.

