Nano Emeralds are not synthetic, they are created; mixes of various oxides, from alumina to zinc, but not Beryl in any shape. Once formed, they have similarities with spinel, gahnite, sapphirine and a hardness of 6.5 to 7 on the Mohs scale
Created gems are simulated: not synthetic. They make excellent and very affordable alternatives. They are not mined, have a smaller carbon footprint and are more environmentally friendly