18 inch necklace extends to 19 inches, closing with a strong lobster clasp. This soft green stone is very high quality, subtle and shining. Green amethyst is not well known yet but it is becoming popular with it's irresistible beauty. The stones are graduated in size, the largest center stone is 9 x18mm, the smallest is 7 x 10mm. So many carats of green amethyst! This is a great deal and a rare piece.