“Each of these types of pyrite tells us something different about our planet, where it came from, about life, and how it has changed over time,” Hazen said.
For this reason, the new papers categorize minerals by “type,” a term Hazen and Morrison define as a combination of mineral species with its mechanism of origin (think volcanic pyrite versus microbial pyrite). Using machine learning analysis, they sifted through data from thousands of scientific papers and identified 10,556 distinct mineral types.
Morrison and Hazen also identified 57 processes which, individually or in combination, created all known minerals. These processes included various types of weathering, chemical precipitation, metamorphic transformation within the mantle, lightning, radiation, oxidation, massive impacts during the formation of the Earth, and even condensations in space. interstellar before planet formation. They confirmed that the greatest contributor to mineral diversity on Earth is water, which, through a variety of chemical and physical processes, helps generate more than 80% of minerals.
But they also discovered that life is a key player: a third of all types of minerals form exclusively as parts or by-products of living things, such as bits of bone, teeth, coral and kidney stones (all of which are rich in minerals), or feces, wood, microbial mats, and other organic materials which, over geologic time, can absorb elements from their environment and transform into something something that looks more like rock. Thousands of minerals are shaped by the activity of life in other ways, such as the germanium compounds that form in industrial coal fires. Including substances created by interactions with byproducts of life, such as oxygen produced during photosynthesis, the fingerprints of life are found on about half of all minerals.
Historically, scientists “have artificially drawn a line between what is geochemistry and what is biochemistry,” said Nita Sahai, a biomineralization specialist at the University of Akron in Ohio who was not involved in the new research. In reality, the border between animal, vegetable and mineral is much more fluid. The human body, for example, contains about 2% minerals by weight, most of which are locked up in the calcium phosphate scaffolding that strengthens our teeth and bones.
The depth of the mineralogy’s intertwining with the biological may not surprise Earth scientists, Sahai said, but Morrison and Hazen’s new taxonomy “has put in a nice systematization and made it more accessible to a larger community.
The new mineral taxonomy will be welcomed by some scientists. (“The old one sucked,” said Sarah Carmichelmineralogy researcher at Appalachian State University.) Others, such as Carlos Gray Santana, a philosopher of science at the University of Utah, support the IMA system, even though it ignores the nature of mineral evolution. “That’s not a problem,” he said, because the IMA taxonomy was developed for applied purposes, like chemistry, mining, and engineering, and it still works great in those areas. . “It’s good for meeting our practical needs.”