By examining diamonds from the 50,000-year-old meteorite, scientists discovered a tiny, fascinating and intricate structure that had never been seen before.
According to the researchers, the structure, which is an interconnected form of graphite and diamond, has special qualities that could one day be used to create even faster charging or new types of electronics.
The 50,000-year-old meteorite, dubbed “Diablo Canyon,” was originally found in Arizona in 1891. This meteorite is composed of about 90% kamacite, about 1-4% taenite, and up to 8.5% graphite-troilite nodules. It is estimated that the rock from which the meteorite came was 30 meters in diameter and around 60,000 tons.
The strange diamond structures are believed to have formed and become trapped in the meteorite during separation from the parent rock, it writes Interesting Engineering.
50,000-year-old meteorite contains strange diamonds
This meteorite contains diamonds, but not the common ones. Most diamonds form nearly 150 kilometers below the Earth’s surface, where temperatures can reach more than 1,093 degrees Celsius. The temperature and pressure at this depth causes the carbon atoms to arrange themselves in cubic shapes.
In contrast, the diamonds found inside the “Diablo Canyon” meteorite have a hexagonal crystal structure and are known as lonsdaleite (named after British crystallographer Dame Kathleen Lonsdale, the first female professor at University College London). It was discovered that these types of crystals can only form at incredibly high pressures and temperatures.
Scientists have successfully made lonsdaleite in the lab using gunpowder and compressed air to propel graphite discs at 15,000 mph (24,100 km/h) toward a wall; lonsdaleite is usually only formed when asteroids hit Earth at enormous speeds.
What surprised the researchers?
Regarding the “Diablo Canyon” meteorite diamonds, scientists noticed an unusual phenomenon while analyzing the lonsdaleite in the meteorite. For example, they found growths of another carbon-based substance called graphene interacting with diamond instead of the pure hexagonal formations they had anticipated.
These growths, called diaphytes, take on the appearance of a particularly fascinating layered pattern inside the meteorite. The “arrangement defects” between these layers indicate that the layers do not line up precisely, the researchers said.
The discovery of diaphyte in lonsdaleite from the 50,000-year-old meteorite raises the possibility that this resource may be widely accessible, as it can be found in other carbonaceous materials, according to the researchers’ findings. The discovery also improves researchers’ understanding of the temperatures and pressures required to build the structure.
The future of graphene
Graphene consists of a layer of carbon one atom thick, arranged in hexagons. The material has many potential applications, even though research into it is still in its early stages.
It could one day be used for more precise medical treatments, smaller electronics with lightning-fast charging speeds or faster, more flexible technology, the researchers said, because it’s as light as a feather and as strong as a diamond , transparent and highly conductive and 1 million times thinner than a human hair.
The 50,000-year-old meteorite has proven very useful for science
Because these graphene growths have been found inside meteorites, researchers can now learn more about how they occur and, consequently, how to create them in a lab.
“By controlled growth of layered structures, it should be possible to design materials that are both ultra-hard and ductile, as well as having tunable electronic properties from conductor to insulator,” said Christoph Salzmann, a chemist at University College London and co-author of the paper describing the research.
The strange new structures were described in the magazine Proceedings of the National Academy of Sciences.