What is the 'weight test' when judging if a diamond is genuine?

What is the 'weight test' when judging if a diamond is genuine?

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When judging whether a diamond is genuine or not using the weight test, one takes a diamond weighing scale, and places the diamond on that scale. If that stone that appears to be a one carat is heavier than a one carat by almost double, about eighty-five percent, then is not a diamond. The most commonly used simulate is cubic zirconium. and a cubic zirconium weighs about eighty-five per cent more than it's similar looking counterpart, a diamond.