The term Simulant literary means to ‘resemble’. The term, when used in the context of antique usually refers to diamond stimulants used in jewelry. The first diamond stimulant to be used was glass. European glass makers of the period used lead oxide to give glass to give it brilliant look. Other common stimulants include Cubic Zirconia, Colour less Synthetic Corundum (sapphire), Synthetic Spinel, Strontium Titanate, Yttrium Aluminium Garnet (YAG), Gadolinium Gallium Garnet (GGG), and Glass (Paste).