Color Change Gemstones and How Gems Change Color: gemSelect

Frequently Asked Questions (FAQ) / Color Change Gems

Why do some gems show a color change?

Color change gems have two approximately equal sized transmission windows. A blue gemstone appears blue because it absorbs all frequencies of light except for blue. A gemstone that absorbs both blue and red light will appear blue when the light is rich in blue wavelengths (e.g. in sunlight or fluorescent light) and red or purple when the light is rich in red wavelengths (e.g. in incandescent light).

View all of our color change gemstones here.

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Overall Rating -> 9

It was fine . Wish there had been more round stones to select from

Posted By Emm in January, 2026

Source: Bizrate

Overall Rating -> 10

They have a wonderful selection of gems of all sorts, shapes, cuts, and quality. I am very particular about the quality of stones I buy, and found many with VVS clarity and excellent cut and polish. I am thrilled with each of the stones I purchased, and would definitely recommend GemSelect to everyone.

Posted By Debsarabs in February, 2026

Source: Bizrate

Overall Rating -> 10

All good

Posted By DouscheGift in August, 2025

Source: Bizrate

Overall Rating -> 10

I loved it! Extensive inventory, great prices, I definitely will be buying from here again!

Posted By Lex in April, 2026

Source: Bizrate

Overall Rating -> 9

Nothing bad to report. Everything is as expected. The gems and the price are all very good.

Posted By Dafanatic in August, 2025

Source: Bizrate

Overall Rating -> 10

I have shopped at Gemselect for nearly 20 years. I especially like that you see pictures of the exact gem you are purchasing. You are a trusted source.

Posted By DNaber in October, 2025

Source: Bizrate

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