Yellow sapphire gemstone (Pukhraj Stone) is a natural occurring gemstone that belongs to the corundum family. As, it is clear from the name that yellow sapphire is a sapphire gemstone. And, sapphires are known for their excellent color and physical properties.
Thus, yellow sapphire is also a special gemstone that embodies all the enrich properties of the sapphire stones. The hardness of the yellow sapphire gemstone is 9.0 on Mohs scale and the refractive index of the stone is 3.99 to 4.01.