RocksdayBlue Lace Agate vs Chalcedony
To tell Blue Lace Agate from Chalcedony: Plain chalcedony lacks the tight lace banding.
Pale blue and white chalcedony with wavy, lace-like bands. The classic rough came from one Namibian mine.
Photo: I2Overcome, CC0
Quartz made of microscopic fibers. Plain chalcedony is soft blue-gray and often grows in bubbly, grape-like crusts.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Key differences
- Plain chalcedony lacks the tight lace banding.
Side by side
| Property | Blue Lace Agate | Chalcedony |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6.5–7 | 6.5–7 |
| Luster | Waxy | Waxy |
| Streak | White | White |
| Colors | Blue, White | Blue, White, Gray |
| Crystal system | Microcrystalline quartz (chalcedony) | Microcrystalline quartz |
| Specific gravity | 2.6–2.65 | 2.58–2.64 |
| Formula | SiO₂ | SiO₂ |
| Found in | Namibia | Oregon; Namibia |
Properties that are the same for both are grayed out.
How to identify blue lace agate
- Soft sky blue and white in wavy bands, not a deep dyed blue.
- Translucent at the edges.
- Hard enough to scratch glass.
Crystal system: Microcrystalline quartz (chalcedony)
Full Blue Lace Agate guide →How to identify chalcedony
- Waxy, translucent and milky.
- Bubbly 'botryoidal' surfaces are common.
- No crystal faces; scratches glass.
Crystal system: Microcrystalline quartz
Full Chalcedony guide →More comparisons
Frequently asked questions
What is the difference between blue lace agate and chalcedony?
Blue Lace Agate is a mineral (SiO₂) with a Mohs hardness of 6.5–7 and a waxy luster, usually blue or white. Chalcedony is a mineral (SiO₂) with a Mohs hardness of 6.5–7 and a waxy luster, usually blue, white or gray.
How can you tell blue lace agate from chalcedony?
Plain chalcedony lacks the tight lace banding.
Could you tell them apart from a blurry close-up?
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