Mahogany Obsidian Slab

Earth's Fiery Origins, Captured in Stone

This striking Mahogany Obsidian specimen weighs 29 grams and features rich swirls of reddish-brown against a deep black volcanic glass matrix. Nicknamed “Volcanic Ironwood” for its dramatic iron-rich banding, it was formed from rapidly cooled lava with high iron content — sourced from ancient volcanic flows in the USA or Mexico. With a naturally polished face and rugged edges, it’s a bold and beautiful piece for collectors, lapidary artists, or display.

Specimen Details

• Specimen: Mahogany Obsidian Slab
• Weight: Approx. 29 grams
• Shape: Irregular slab
• Origin: Likely USA or Mexico
• Condition: Natural slab with one broken edge; polished face
• Color: Black with reddish-brown banding
• Composition: Volcanic glass with iron inclusions
• Chemical Family: Silicate
• Formation: Rapidly cooled lava with high iron content
• Hardness: 5–5.5 on Mohs scale
• Nickname: “Volcanic Ironwood”

Note: Some photographs were taken while the specimen was wet to enhance its natural colors.