Carnelian Agate
Chalcedony (Silicon Dioxide, SiO2)
Rock Type: mineral

Physical Properties
Hardness: 6.5–7 on Mohs scale; Color: Translucent orange to reddish-brown; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58–2.64
Formation & Geological History
Formed through the deposition of silica from groundwater in the cavities of igneous rocks, particularly volcanic lavas. The orange hue is caused by iron oxide impurities.
Uses & Applications
Commonly used in lapidary work for cabochons, beads, and carved jewelry. It has a high historical value for seals and amulets.
Geological Facts
In ancient times, carnelian was believed to give courage in battle. It was widely used in ancient Egypt and Rome for signet rings because hot wax does not stick to it.
Field Identification & Locations
Identify in the field by its waxy texture and translucent orange color when held to light. Look for it in riverbeds or gravel deposits in volcanic regions like Brazil, India, or the Pacific Northwest, USA.
Identified on: 4/22/2026
Mode: Standard