Is It Possible To Break Obsidian

2 min read 28-12-2024

Obsidian, with its alluring glassy sheen and sharp edges, holds a certain mystique. But beyond its aesthetic appeal lies a question of practicality: just how strong is this volcanic glass? The answer, as with most things, is nuanced.

The Hardness of Obsidian

Obsidian's hardness, measured on the Mohs Hardness Scale, sits around 5 to 5.5. This means it's harder than glass (around 5) but softer than quartz (7). While this might seem relatively hard, it’s crucial to understand that hardness doesn't equate to unbreakable. Obsidian's hardness refers to its resistance to scratching, not its resistance to fracturing or shattering.

Factors Affecting Obsidian's Fragility

Several factors influence how easily obsidian breaks:

1. Conchoidal Fracture: Obsidian's defining characteristic is its conchoidal fracture. This means it breaks along smooth, curved surfaces, like the inside of a seashell. This fracture pattern, while aesthetically pleasing, also makes it inherently brittle and prone to shattering under impact.

2. Internal Flaws and Stress: Like any natural material, obsidian can contain internal flaws, micro-fractures, and stress points. These imperfections act as weak points, significantly reducing its overall strength and making it susceptible to breakage under relatively low stress.

3. Type of Obsidian: The specific type of obsidian, its mineral composition, and cooling process can affect its durability. Some obsidian types might be slightly more resistant to fracturing than others, although overall, obsidian remains a relatively fragile material.

4. Impact and Force: The type and amount of force applied directly impact the likelihood of breakage. A sharp blow, even a relatively minor one, can easily cause obsidian to shatter. Conversely, gradual, sustained pressure might lead to cracking or splitting over time.

Breaking Obsidian: Methods and Precautions

Breaking obsidian intentionally requires care and the appropriate tools. While it can be chipped with a hammer, using specialized tools designed for rock splitting is recommended to minimize the risk of injury. Protective eyewear and gloves are essential, given the sharp, jagged edges produced when obsidian breaks.

Conclusion: It's Breakable, But with Caution

While obsidian possesses a certain level of hardness, its inherent brittleness makes it relatively easy to break. Understanding its conchoidal fracture pattern and the impact of internal flaws is key to handling obsidian safely and responsibly. Whether you're admiring it in a museum, working with it as a craftsman, or simply handling a piece of this intriguing volcanic glass, awareness of its fragility is crucial to prevent accidental damage or injury.