This is a necklace made of 10kt yellow gold with a pear-shaped lab-created amethyst and small round diamonds. It weighs about 2 grams and has a total gemstone weight of half a carat. The amethyst is a flawless purple color and is held in place by prongs. The diamonds have a slightly lower clarity and are set in prongs as well. The total carat weight of the diamonds is 0.12. There is no third gemstone included in the necklace.Precious Metal Type: 10kt Yellow Gold Approx. Gram Weight: 1.97394 Total Gemstone Carat Weight: 1/2 Primary Gem Type: Lab Amethyst Primary Gem Shape: Pear Primary Gem Color: Purple Primary Gem Clarity: Flawless Primary Gem Setting: Prong-set Primary Gem Carat Weight: 0.42 Gem2 Type: Diamond Gem2 Shape: Round Gem2 Color: G-H Gem2 Clarity: I2-I3 Gem2 Setting: Prong-set Gem 2 Carat Weight: 0.12 Gem 3 Carat Weight: None