Here’s what you’ll learn when you read this story:Precious metals are leaking out of Earth’s core into the mantle, a new study suggests. Scientists identified a particular isotope of ruthenium (Ru) in volcanic rock samples—a form that typically only occurs in Earth’s core. 99.999 percent of Earth’s precious metals lay hundreds of miles beneath the surface, trapped inside the planet’s molten core. According to a new study published in the journal , Earth’s core is “leaking” gold. Scientists discovered traces of Ru while studying samples of volcanic rocks from Hawaii and concluded that they must have come from Earth’s core.