Gemstone Optical Properties

Step 2: Advanced Gemology

Lesson 1

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We tend to take light for granted. It’s such a common thing we experience every day. Rarely do we think of the scientific definition of light or its properties. However, in the gemological world, light plays a critical role. You must first understand the principles of light before understanding gemstone optical properties. Gemologists can analyze these properties for gemstone identification. They can also apply them practically when cutting gems for optimum brilliance and character.

The Properties of Light

Electromagnetic Energy

Light is part of the electromagnetic spectrum, one of the fundamental energies of the universe. It’s present everywhere in substantial amounts.

Light energy travels in waves. The energies on the electromagnetic spectrum differ simply by their wavelengths. Some are shorter, some longer. Wavelength has nothing to do with the amount of energy carried. Wave amplitude determines that. All wavelengths can be high or low in energy.

Although, in nature, all electromagnetic energy is essentially the same, varying wavelengths have different characters. For example, we relate to some as radio waves, others as X-rays. We see a very tiny part of the electromagnetic spectrum as light. Within this section, we perceive …