S1E65 - The Most Dangerous Rock In Hannah's Collection

When you think of dangerous geological specimens, does your mind jump straight to radioactive uranium, toxic heavy metals, or even asbestos? What if one of the most dangerous items sitting on a shelf is actually a polished, perfectly ordinary-looking piece of black obsidian?

Professor Hannah Fry and Michael Stevens dive into the surprisingly treacherous geology and chemistry of obsidian.

Hannah brings an onyx from her personal rock collection to explain exactly why this specific piece of material holds the title of the most dangerous rock she owns, unpicking the fascinating physical properties of...