14kt gold filled, natural, undyed, untreated aquamarine, light blue.Doesn't get black, It comes with a 3 year guarantee.this necklace is delicate, but with a lot of presence! It's 15.3 inches long & has a beautiful extending chain with many more options till 20.3 inches, so you can also combine it well with other necklaces! For special requirements feel free to convo me (: