Glass looks fake and is of low hardness, color also can fade away with time
Cubic Zirconia (CZ) has too high brilliance i.e. RI, which is why it’s still the best affordable imitation of Natural Diamond. But it’s not perfect for imitating Natural Color Stones… besides color is fading over time.
Synthetic Corundum and Created Materials – are too expensive… And it’s not possible to cut really big sizes..due to limitation of rough size.
Nanocrystal® on the contrary completely imitates brightness and colors, as well as relatively close in hardness and density of many gemstones: Emerald, Sapphire, Topaz, Aquamarine, Citrine, Peridot, Garnet, Kunzite, Morganite, Grey and Smoky Quartz; Ivory (beige-cream), Turquoise, Aqua blue opal, Black and many others – totally more than 155 different colors and shades …
Most of the Nanocrystals® are offered in different variations of color saturation: Very Dark, Dark, Medium and Light. The darker varieties are used for producing smaller sized stones, while the lighter selections are used for larger ones; this enables a manufacturer to maintain the same hue of color saturation throughout variations in sizes and shapes.