Rock Identifier
Crazy Lace Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral
mineral

Crazy Lace Agate

Chalcedony (Silicon Dioxide, SiO2)

Hardness: 6.5–7 (Mohs scale); Color: Variegated swirls of white, brown, grey, and occasional reds; Luster: Waxy to vitreous; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58–2.64

Hardness
6
Color
Variegated swirls of white, brown, grey, and occasional reds
Luster
Waxy to vitreous
Identified More mineral

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Hardness: 6.5–7 (Mohs scale); Color: Variegated swirls of white, brown, grey, and occasional reds; Luster: Waxy to vitreous; Crystal Structure: Trigonal (Microcrystalline); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58–2.64

Formation & geological history

Formed through the deposition of silica-rich groundwaters in volcanic rock cavities (vesicles). Originates specifically from the Cretaceous period (approx. 65–90 million years ago) specifically in Chihuahua, Mexico.

Uses & applications

Predominantly used for lapidary work, jewelry (cabochons, beads), decorative carvings, and as a popular specimen for collectors and metaphysical practitioners.

Geological facts

Known as the 'Laughter Stone' or 'Mexican Lace Agate,' it is unique because it is found in only one place in the world: the state of Chihuahua in northern Mexico. Its complex banding is caused by rhythmic crystallization and iron/aluminum impurities.

Field identification & locations

Identify in the field by its distinct 'botryoidal' or 'lace-like' concentric banding and its high hardness (it will scratch glass). Look for it in limestone or volcanic host rocks in the Sierra Madre Mountains of Mexico.