We had a suspect in for examination recently, with this large green oval 'emerald'. At first glance it does indeed look a bit like an emerald, but as always experience gives us a feeling about the stones that have something wrong with them and we investigate thoroughly to find out why. Closer examination showed that looking sideways through the stone's girdle displayed a divide in colour, with the lower half looking almost colourless. Placing the stone in immersion fluid greatly increased the difference making x3 different layers visible. The stone is actually a composite called a triplet, sometimes referred to as a Soudé Emerald with this type of emerald look-a-like. Although glass or garnet are the most common materials in composites, this one is actually made from a green adhesive layer sandwiched between x2 layers colourless Quartz. Gemstone testing is just one of the services we offer. If you have any doubts with the stones you have in stock send them through for us to evaluate - it's not worth mis-selling a dodgy stone to your customers!