This yellow tourmaline with a green wash does not have particularly good crystal, because it has a wide assortment of faint wispy feathers. It is flashy and about average in brightness, despite the fact, that yellow greens usually have higher brightness levels, than most colors of tourmaline. So what makes this standard round brilliant with a nice, but not exceptional color, more interesting than usual. It has copper in it as a chromophore. A chromophore is a trace element that effects the color of the gemstone that it is dissolved in. I found copper’s signature absorption peaks with my spectrometer. I have no idea how much effect the copper is having on the color of this gemstone, but the copper is interacting with the light coming into the gem, in the visible light range. The gemstone weighs 3.35 carats.