A market-wide average across qualities and sizes. Your stone's value depends on carat, color, clarity, cut, treatment, and origin.
Chalcedony is a microcrystalline variety of quartz composed of intergrown quartz and moganite, occurring in a broad range of colors and patterns. In its narrow sense, 'chalcedony' often refers to translucent to opaque, unbanded material in soft blue, gray, white or other pastel hues. It has Mohs hardness about 6.5–7 and good toughness.
Market averages will not price your stone. GemstoneAI identifies gems and jewelry from a photo, checks authenticity and treatment signals, and gives you a real market valuation in seconds. Free to try.
The GemstoneAI market index for chalcedony is $10 per carat as of 2026-08-04. That is a market-wide average across qualities, not a quote for a specific stone. Individual value depends on carat, color, clarity, cut, treatment, and origin.
Visual tests alone are unreliable. GemstoneAI analyzes a photo of your stone for identity, treatment indicators, and authenticity signals, then estimates market value. It is free to try.
Over the past 30 days the chalcedony index moved +2.5%. Gem prices move on supply, demand, and metal markets; treat any single stone as a collectible first and an asset second.