The world’s most expensive substances command their prices for very different reasons. Some, like rare gemstones, are ...

Some items carry a price so steep that gold barely registers beside them. These materials come from unusual places: deep geological layers, rare biological sources, and in a few cases, far beyond our ...

When we think of the most expensive items in the world, our minds often wander to priceless jewels, rare metals, or perhaps extravagant real estate. However, there’s a substance so rare and costly ...