Trusted gemstone information, in plain English.
Clear, accurate profiles of the world's gemstones, the complete birthstone chart, and honest guidance on buying and caring for them, with none of the jargon.
Your starting point for learning about gems
The Encyclopedia
In-depth profiles with real gemological properties, treatments, and care.
Browse gems »Birthstones
The full month-by-month chart, modern and traditional, and what recently changed.
See the chart »Buying & Care
How to judge color and treatments, and how to keep every gem looking its best.
Read the guides »Explore the encyclopedia
Start with six of the world's most important gemstones, each with a full properties table and honest care advice.
Learn before you buy
Plain-English answers to the questions gem buyers actually ask.
Birthstones by Month
The complete chart, modern and traditional, plus what changed in 2016.
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Hardness & Wearability
Why the hardest gem still isn't unbreakable, and which stones suit daily wear.
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How to Buy a Gemstone
Color, clarity, treatments and reports, without the sales pitch.
Read more →Written by people who love gems
We publish clear, accurate gemology from gemologists, jewelers, and lapidaries. If you know the field, we would love your work.
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