A Jeweler's Guide to the 7 Types of Mexican Obsidian | New Stone Age Cabochons
TLDR: Obsidian is natural volcanic glass. The 7 main Mexican types are identified by their inclusions: trace minerals create mahogany (iron) and snowflake (cristobalite), while trapped gas or water creates sheen, rainbow, and velvet types. Peanut is the rarest.
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How to Identify the 7 Different Types of Mexican Obsidian
As an artist, choosing your stone is the start of your creative story. Mexican obsidian is legendary not just for its sharpness, but for the incredible variety of colors and patterns hidden within the dark glass.
Here is your guide to identifying the 7 types you’ll encounter, ranked generally from most common to most rare.
| Obsidian Type & Description | Example Image |
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1. Black Obsidian Deep, glossy, and endlessly versatile. Pure volcanic glass with no inclusions, showing a smooth conchoidal fracture. Maker Tip: Ideal for sleek minimalist jewelry or as a neutral base in beadwork. |
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2. Sheen Obsidian (Gold & Silver) Appears black but flashes metallic gold or silver under light, caused by tiny trapped gas bubbles. Identification: Rock the stone under light to see the shifting sheen. |
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3. Snowflake Obsidian Displays white “snowflake” patterns formed by cristobalite crystals within the black glass. Maker Tip: Excellent for high-contrast, graphic designs. |
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4. Mahogany Obsidian Rich reddish-brown swirls or patches caused by iron oxide inclusions. Maker Tip: The warm “wood grain” look complements rustic or nature-inspired jewelry. |
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5. Rainbow Obsidian Appears black until sunlight reveals vivid rainbow rings or bands caused by magnetite layers. Maker Tip: Set open-back to allow light to reveal the colors. |
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6. Velvet Obsidian (Manto Huichol) Features swirling, iridescent “crushed velvet” textures from folded lava flow. Maker Tip: Highly sought after for statement jewelry; each cabochon is unique. |
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7. Peanut Obsidian Extremely rare. Displays red or orange “peanut-like” orbs (feldspar crystals stained by hematite) in dark matrix. Maker Tip: True collector’s stone — a conversation piece for custom designs. |
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✨ Bonus Rarity: Fire Obsidian Ultra-rare variety with a fiery holographic iridescence from botryoidal magnetite layers. It is one of the most prized natural glasses on earth and if found in Oregon, USA. |
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Quick Facts for Makers
| Scientific Name | Amorphous Volcanic Glass (Mineraloid) |
| Common Names | Obsidian, Volcanic Glass, Apache Tear |
| Common Imitations | Man-made black glass, green “obsidianite,” or dark resins |
| Mohs Hardness | 5.0–5.5 (soft & brittle) |
| Color Variations | Black, brown, and all 7+ types above |
| Origins | Mexico, USA (Oregon, California), Iceland, Italy |
| Price Range | $–$$$$ (Black affordable, Peanut/Fire very rare) |
| Best Quality Indicators | Glassy luster and vibrant patterns for special types |
Care & Cleaning Quick Tips
- Use a microfibre cloth to remove fingerprints and dust.
- Obsidian is brittle — avoid impact or dropping.
- Store separately to prevent scratching by harder stones.
Shop Our Ethically-Sourced Obsidian Cabochons
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FAQ
Is obsidian a good stone for jewelry making?
Yes! It’s affordable, beautiful, and takes a high polish. Because it’s glassy and brittle, it’s best for pendants and earrings rather than heavy-wear rings.
What’s the difference between rainbow and sheen obsidian?
Sheen obsidian has a gold or silver metallic flash. Rainbow obsidian reveals colored rings or layers (purples, greens, blues) that appear under direct light.
How can I tell if my obsidian is fake?
Natural obsidian shows subtle inclusions or gas bubbles. Perfectly clear black glass is often synthetic. Buy from reputable lapidary sources.
What’s the rarest type of obsidian?
Peanut Obsidian from Sonora, Mexico, is the rarest of the seven types. True Fire Obsidian from Oregon USA is even rarer, prized for its fiery holographic sheen.
Is obsidian safe to work with for jewelry making?
Yes, but wear a respirator when cutting or grinding, obsidian dust contains silica and should not be inhaled.