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Obsidian: The Sharpest Rock on Earth (and in Surgery)

Obsidian: The Sharpest Rock on Earth (and in Surgery)

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In this third Volcano Minisode, Katy digs into one of the coolest things a volcano has ever made: obsidian—a rock so sharp it's been shaping human history for 30,000 years and is still used in modern surgery. 🔪🖤

🌋 What exactly is obsidian and how is it formed?
⚡ How can lava turn into volcanic glass in a flash?
🩺 Why are obsidian scalpels sharper than steel—and still used today?
🛡 How did ancient people turn this into tools, weapons, and even mirrors?

From Stone Age scrapers to eye surgery scalpels, obsidian proves that volcanoes don’t just destroy—they create tools that changed the course of human evolution.

👉 This is episode 3 of 6 in our Volcano Minisodes series—bite-sized, bizarre, and bursting with molten-hot science facts.

🎧 Listen now to discover why this rock deserves way more credit.

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