Answers for the Teacher Only

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What Do You Think?

A jeweler with a trained eye can identify a diamond with a careful look. A diamond reflects more light than cut glass, because of the diamond’s greater index of refraction. The diamond also has a range of color not found in glass and also particular small imperfections. Despite these visual differences, many jewelers rely on an electrical device that applies a small amount of heat to an unknown stone and identifies a diamond from the resulting temperature change.