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How to buy gemstones online

GOOD EYE.
GREAT QUESTIONS.

Found a stone that speaks to you? Get to know it. Here are five things to check before making it yours.

Your before-you-buy companion / General guidance, not gemstone grading

01 / Colour & photographs

A first impression.
Then a closer look.

Give every photograph in the listing a moment. Compare the face-up view with the side and back. Watch any available video to see what changes as the stone turns.

Lighting and your screen can influence the colour you see. Ask how the photographs were taken and whether other views are available. An image can show you a look you love; it cannot establish identity, treatment status or geographic origin.

A good question

“Could I see this piece from another angle and in different lighting?”

02 / Weight, size & fit

Carats tell one story.
Dimensions tell another.

A metric carat is 0.2 grams: it describes weight. To understand the size of a gemstone, look for its measurements in millimetres as well. Weight alone won’t tell you how much space it will take up in a setting.

Carats / ct The stone’s weight
Millimetres / mm The physical dimensions

Have a jewelry project in mind? Ask your jeweler whether the shape and measurements will work with the intended setting. For a finished piece, check the size and fit information before choosing.

Reference: GIA’s explanation of metric carat weight .

03 / Material & treatments

Beautiful colour.
Clear information.

Read how the listing identifies the material. Then look for treatment disclosures. If either is unclear, request a written explanation before purchasing. Colour by itself tells you nothing certain about whether a gemstone has been treated.

Care is part of the conversation, too. Ask about the requirements for that particular stone and its treatment history, especially if you plan to have it set in jewelry.

A good question

“How is this material described, what treatments are disclosed, and does it need any special care?”

For an example of material-specific guidance, see GIA’s ruby buyer’s guide. Its advice about ruby should not be treated as a rule for every gemstone.

04 / Reports & paperwork

Read what’s included.
And what it actually says.

Start with the listing: is a laboratory report offered for this piece? If so, ask for the laboratory’s name and a readable copy. Confirm which documents come with your purchase, and compare the report’s description and dimensions with the stone being offered.

A report’s scope matters. GIA’s coloured stone reports address identity, natural or synthetic status, and detectable treatments. Geographic origin is available for certain stones when determinable. Another laboratory’s report may cover different information.

Use the issuing laboratory’s verification service where available. A mention of a report is a starting point for reading it, not a reason to skip the details.

A good question

“Which laboratory issued the report, can I read it, and is it included with this piece?”

Reference: GIA’s coloured stone report services .

05 / Before you make it yours

All eyes.
All the details.

Keep the listing open and work through this quick checklist. A question still unanswered? Ask before checkout.

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GOOD EYE.
GO ROGUE.

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