AltGems
Updated as of June 2026

Onyx buying guide

Use this checklist to choose a onyx you will be happy with, then compare prices across a couple of trusted sellers.

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The Onyx buying checklist

FactorWhat to look for
ColorEven, saturated tone in black or white or banded. Color drives value most.
CutSymmetry and life. A good cut makes a stone look larger and brighter.
ClarityEye-clean is the practical target for most buyers.
TreatmentDyeing (most black onyx). Ask the seller to disclose.
Budget$3 to $40 per carat is the typical range.
MetalPairs well with sterling silver, white gold, yellow gold.

Best metals for Onyx

Onyx looks best set in sterling silver, white gold, yellow gold. See our metal guides to compare durability and cost.

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Frequently asked questions

What should I look for when buying Onyx?
Prioritize color and cut, confirm any treatment, set a carat target for your budget, and pick a metal that suits the stone. Onyx pairs well with sterling silver, white gold, yellow gold.
Where is the best place to buy Onyx?
For fine pieces, established jewelers with return policies and lab reports are safest. For unique or budget pieces, vetted marketplace sellers work well. Always check reviews and the return window.
Should I choose natural or lab-created Onyx?
Natural Onyx carries origin appeal, while lab-created alternatives can cost less for similar looks. Choose based on budget and what matters to you.