Curated playlist
Building materials
- ConcreteConcrete is the second-most-used substance on Earth, behind only water. Its cement causes about 8% of world emissions.
- Stainless steelStainless steel began as a failed search for better gun barrels. Harry Brearley found it in Sheffield in 1913.
- AluminiumAluminium is the most abundant metal in Earth's crust, yet for most of history no one had seen any.
- BrickThe oldest known bricks were made of river mud and dried in the sun. They date to before 7500 BC at Tell Aswad.
- SteelIn 327 BC, the defeated King Porus gave Alexander the Great 30 pounds of steel. He chose it over gold or silver.
- IronThe earliest iron tools were hammered from rocks that fell from the sky.
- CementCement does not harden by drying out. It sets through reactions that need water.
- Roman concreteLime lumps in Roman concrete were once blamed on sloppy mixing, but they help it heal.
- Cast ironA cast-iron railway bridge collapsed under a train in May 1847, killing five people.
- WoodA tree can thrive with its heart completely decayed. Heartwood is named only for its position in the trunk.
- MasonryA brick wall that curves back and forth is harder to topple than a straight one.
- SlateSlate can lose up to 50 percent of its original volume as mud squeezes into rock. It sometimes still preserves fossils.