mineral
Orange chalcedony geode
Microcrystalline quartz (SiO₂), commonly called carnelian or orange agate when strongly colored
AI-generated identification · may be incorrectMohs hardness 6.5–7; translucent orange to reddish-brown, waxy to vitreous luster, cryptocrystalline quartz with conchoidal fracture and no cleavage. The cavity is lined with tiny quartz druzy crystals; iron oxides likely produce the color.
Identified More mineral →
Explore Orange chalcedony geode in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 6.5–7; translucent orange to reddish-brown, waxy to vitreous luster, cryptocrystalline quartz with conchoidal fracture and no cleavage. The cavity is lined with tiny quartz druzy crystals; iron oxides likely produce the color.
Formation & geological history
Silica-rich groundwater filled cavities in volcanic rock, depositing chalcedony and later quartz crystals. The specimen’s exact age and host locality cannot be determined from the image; geodes commonly form in Cenozoic to Mesozoic volcanic rocks.
Uses & applications
Used as an ornamental specimen, carving material, beads, cabochons, and occasionally jewelry; attractive geodes are primarily collector pieces rather than construction stone.
Geological facts
Orange chalcedony grades into carnelian, while banded varieties are called agate; these names overlap based on color and pattern. The rough, natural cavity and druzy lining distinguish it from dyed or molded glass.
Field identification & locations
Identify by its waxy translucence, conchoidal fracture, quartz-like druzy, and lack of visible cleavage; common sources include Brazil, Uruguay, Madagascar, India, and Mexico. Avoid prolonged heat or harsh chemicals, which can alter color or damage crystals.
