How to identify sapphire rough
A small sapphire will cost tens of thousands of yuan. There are many counterfeit sapphires on the market today, so it is necessary to learn to identify sapphire rough. How to identify the original sapphire stone?
Identifying sapphire rough is to distinguish sapphire from other blue gems. Since the sapphire has a Mohs hardness of 9, second only to diamonds, other counterfeit products are lower than it. As long as the sapphire is scribbled with standard hardness such as topaz and crystal to determine the hardness, it is roughly sapphire.
In addition, sapphire and other confusing products can be distinguished based on other characteristics such as specific gravity and refractive index.
The sapphire has a hardness of 9, a specific gravity of 3.97 to 4.08, and a refractive index of 1.766 to 1.744.
The blue spinel has a hardness of 8, a specific gravity of 3.6 to 3.8, and a single refractive index of 1.72.
The blue tourmaline has a hardness of 7, a specific gravity of 3.05, and a refractive index of 1.62-1.65.
Tanzanite has a hardness of 6.5-7, a specific gravity of 3.5, and a refractive index of 1.69-1.70.
Dong Qingshi has a hardness of 7, a specific gravity of 2.59, and a refractive index of 1.54-1.55.
The blue cone ore has a hardness of 5-5.6, a specific gravity of 3.67, and a refractive index of 1.78.
Kyanite has a hardness of 4-6, a specific gravity of 3.69, and a refractive index of 1.72.
Although there are many counterfeit sapphire products on the market, as long as you understand the sapphire characteristics, it is still easy to distinguish.
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