What if we told you that peanut butter could be turned into diamonds?
It sounds like something out of a sci-fi novel, but it’s actually happening in a lab in Germany.
Scientists at the Bayerisches Geoinstitut are working on recreating the extreme conditions found deep within the Earth’s mantle—a layer that makes up about 85% of our planet’s total mass.
In the process, they’ve stumbled upon an unexpected side effect: they can manufacture diamonds using everyday materials, including peanut butter.
While this might sound like a bizarre party trick, it’s part of a much bigger scientific mission.
The team, led by geochemist Dan Frost, is trying to solve one of Earth’s greatest geological mysteries: where did all the silicon go?
The answer could reshape our understanding of the planet’s formation.
Crushing Rocks to Uncover Earth’s Secrets
To understand the makeup of Earth’s mantle, scientists need to recreate the crushing pressures and searing heat found beneath the surface.
The Bayerisches Geoinstitut does this by squeezing tiny rock samples under conditions that mimic those hundreds of kilometers underground.
The team uses two types of presses to achieve this.
The first involves a powerful piston that subjects crystal samples to pressures 280,000 times greater than Earth’s atmosphere while simultaneously cooking them in a furnace.
This simulates the top layers of the lower mantle, which sit between 800 and 900 kilometers (500-560 miles) beneath our feet.
At these depths, minerals rearrange into denser structures, revealing clues about the deep interior of our planet.
For deeper layers, the researchers use something even more extreme: an anvil made from two tiny diamonds.
This setup allows them to exert pressure more than 1.3 million times that of Earth’s atmosphere—the kind of force that exists near the Earth’s core-mantle boundary.
But here’s the genius part: while the minerals are still crushed inside the anvil, Frost measures how sound waves travel through them.
This data is then compared to seismic waves recorded during earthquakes and volcanic eruptions, helping scientists determine whether their lab-created materials truly match what’s found deep inside the planet.
The Silicon Mystery—And a Radical New Possibility
For years, scientists believed that Earth’s mantle was primarily made up of the same meteorite material found in asteroids.
However, Frost’s experiments suggest something doesn’t add up.
The mantle appears to have less silicon than expected.
So where did it go? There are two competing theories:
- The silicon sank deeper, right through the mantle and into the inner core.
- It went the other way—into Earth’s crust. If that’s the case, it may have been blasted into space by massive meteorite impacts billions of years ago.
This second idea is especially intriguing.
If Earth’s crust was once rich in silicon, only to lose it through violent space collisions, it could challenge traditional ideas about how our planet evolved.
Could early Earth have been more like the Moon, with a different mineral composition altogether?
Frost and his team are now exploring this possibility.
The Accidental Discovery
While investigating how certain geological processes could have pulled carbon dioxide from ancient oceans into rocks, Frost found himself exploring the formation of diamonds.
Over billions of years, carbon trapped inside Earth’s mantle undergoes extreme heat and pressure, eventually transforming into diamonds.
But creating this process in a lab is notoriously difficult.
And yet, Frost and his team did it—accidentally.
By squeezing carbon-rich materials under high pressure, they successfully formed diamonds. One of those materials? Peanut butter.
Speaking with BBC Future, Frost explained how, at the request of a German TV station, he attempted to make diamonds from carbon-rich peanut butter.
The experiment wasn’t flawless—hydrogen released during the process disrupted the experiment—but, incredibly, some peanut butter still turned into diamond.
The Bigger Picture—And Why This Matters
Of course, peanut butter isn’t about to become a viable source of lab-grown diamonds anytime soon.
The process is slow, requiring weeks to grow even a tiny gemstone.
But the implications are massive.
These experiments help scientists reconstruct Earth’s geological history.
By mimicking the conditions deep inside our planet, researchers can answer fundamental questions: How was Earth formed?
What materials make up its deepest layers?
And, crucially, how do natural processes like carbon storage impact our climate over millions of years?
Frost’s work also has implications for space exploration.
If scientists can recreate the high-pressure conditions found inside planets, they can better understand the makeup of other worlds—including exoplanets in distant star systems.
Some researchers even speculate that similar diamond-formation processes may be happening on icy planets like Neptune and Uranus, where extreme pressures squeeze carbon into diamond rain.
Final Thoughts
While Dan Frost probably won’t be launching a peanut butter diamond business anytime soon, his research is pushing the boundaries of what we know about our planet and beyond.
From solving the mystery of Earth’s missing silicon to shedding light on diamond formation, these experiments are more than just scientific curiosities—they unlock clues about our past, present, and future.
And who knows?
Maybe one day, the knowledge gained from crushing rocks and peanut butter could lead to revolutionary discoveries in materials science, geology, or even space exploration.
Sources: BBC Future
