About this stone
Color
BlueGrayWhiteLavender
Origin
NamibiaTurkeyIndonesiaUSABrazil
Mohs hardness
6.5–7
Treatment categories
NaturalDyed
Industry-standard treatment
Most natural; some color variants dyed
Mineral chemistry
Cryptocrystalline silica — intergrowth of quartz and moganite
Crystal system
Trigonal
Stone family
Chalcedony
Common cuts
RoundFaceted Rondelle
Common sizes
4mm6mm8mm10mm
Care notes
Durable (Mohs 6.5–7). Mild soap and soft cloth.
Related stones
Agate, Carnelian, Onyx, Chrysoprase
Frequently asked questions
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What is chalcedony?
Chalcedony is microcrystalline quartz — silica composed of densely packed fibrous crystals too fine to see with the naked eye, giving the stone its characteristic smooth waxy luster and translucent-to-semi-translucent body. In mineralogy, "chalcedony" is the umbrella term for the whole microcrystalline quartz family (agate, carnelian, onyx, jasper, and others are all chalcedonies). In the bead trade, the name has narrowed to mean the translucent waxy material in soft blue, lavender, pink, green, and white that doesn't fall into one of the named sub-varieties. -
What's the difference between chalcedony and agate?
Agate is a banded chalcedony — chalcedony deposited in rhythmic crystalline layers that produce its diagnostic bands. Trade chalcedony is the unbanded form: smooth, translucent, no rhythmic layering. Both are microcrystalline quartz, both are Mohs 6.5–7, both take the same care. The visual difference is bands (agate) vs. no bands (chalcedony). -
Is blue chalcedony dyed?
Some is, some isn't. Natural blue chalcedony — particularly from Namibian and Turkish deposits — is a soft, slightly variable blue from trace mineral content in the rough. Dyed "blue chalcedony" in the market is typically dyed white chalcedony or dyed agate sold under the chalcedony name; the saturated, perfectly even, slightly-too-vivid blue is the dye signal. Treatment status should be disclosed — ask before buying if it isn't specified. -
How durable is chalcedony for daily wear?
Mohs 6.5–7 — durable enough for any jewelry application, including rings, bracelets, and necklaces. Standard care: wipe with a soft cloth and mild soap; avoid ultrasonics and steam cleaning on dyed material. Natural chalcedony has no fade risk and no special handling requirements. -
What colors does chalcedony come in?
Natural chalcedony's palette is pastel: soft blue, lavender, pink, green, white, occasional tan and gray. Saturated jewel tones — vivid pink, magenta, neon green, electric purple — are dye signals. Dakota's active inventory is blue-dominant with smaller numbers of green, pink, and tan strands; full color and size availability is filterable in the grid above.