mineral

Tumbled banded agate (likely blue lace agate)

Microcrystalline quartz, SiO₂ (chalcedony variety)

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; translucent pale blue, white, and gray banding; waxy to vitreous luster; cryptocrystalline quartz with no visible cleavage and conchoidal fracture. The smooth shape indicates tumbling and polishing.

Identified September 17, 2026More mineral →

Explore Tumbled banded agate (likely blue lace agate) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities in volcanic rocks, depositing successive chalcedony layers; banding commonly developed over millions of years, often in Cenozoic volcanic terrains.

Uses & applications

Used for cabochons, beads, carvings, ornamental objects, and lapidary collections; generally modest commercial value unless strongly colored, naturally patterned, or exceptionally transparent.

Geological facts

Blue lace agate is prized for delicate lace-like blue-and-white bands, though many commercial pieces are simply pale banded agate. Color may be enhanced by dyeing, but this specimen’s subdued appearance is consistent with natural material.

Field identification & locations

Identify by curved parallel bands, translucency, glassy/waxy surface, and inability to scratch it with a steel knife; it should scratch ordinary glass. Common sources include Namibia, Botswana, Brazil, Uruguay, and Mexico.