igneous
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)
Hardness: 5.0–5.5 on the Mohs scale; Color: Reddish-brown (mahogany) and black mottled patterns; Luster: Vitreous (glassy); Crystal Structure: Amorphous; Cleavage: None (conchoidal fracture); Specific Gravity: 2.35–2.6
- Hardness
- 5
- Color
- Reddish-brown (mahogany) and black mottled patterns
- Luster
- Vitreous (glassy)
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5.0–5.5 on the Mohs scale; Color: Reddish-brown (mahogany) and black mottled patterns; Luster: Vitreous (glassy); Crystal Structure: Amorphous; Cleavage: None (conchoidal fracture); Specific Gravity: 2.35–2.6
Formation & geological history
Formed when felsic lava cools rapidly with minimal crystal growth. The reddish color comes from inclusions of Magnetite or Hematite (iron oxides) during the cooling process. Commonly found in areas with geologically recent volcanic activity.
Uses & applications
Used primarily for lapidary work, jewelry (beads, cabochons), ornamental carvings (like the tower shown), and by collectors or practitioners of metaphysical healing.
Geological facts
Despite being called a rock, it is technically a 'mineraloid' because it lacks a crystal structure. Mahogany Obsidian is particularly known for having 'softer' energy in metaphysical circles compared to Black Obsidian.
Field identification & locations
Identify by its distinctive brick-red and black swirling patterns and its sharp, shell-like (conchoidal) fractures if chipped. Common locations include the Western USA (Oregon, California), Mexico, and Japan.
