Human activity has been profoundly altering the environment for a very, very long time. Climate change, selective breeding, other human-derived evolutionary pressures, and human-mediated invasive species are all obvious examples of how we are considerably altering our surroundings.
A recent paper by Robert Hazen of the Carnegie Institution for Science along with Edward Grew, Marcus Origlieri, and Robert Down, is illuminating something less obvious. Humans are significantly altering the mineral diversity of Earth.
Mineral diversity isn’t as popular a topic as biodiversity. There aren’t exactly “save the rocks” campaigns blanketing your newsfeeds. Humanity has collectively failed to bat an eye at any changes to the distribution and diversity of Earth’s minerals. Meanwhile, at least 208 minerals have been ushered into existence as the direct result of human activity.
In their paper, the researchers describe how they meticulously searched through the records of the International Mineralogical Association (and here). There, they discovered numerous examples of minerals that were collected outside of their natural areas of occurrence. They also uncovered more than 80 minerals that have no known natural occurrence at all on Earth. In other words, these minerals are the direct result of human activity. Without humans doing what humans do, they would not be present on this planet.
Perhaps unsurprisingly, many of these out-of-place minerals were associated with mining activities. In all, the paper identified seven key mine-related drivers of mineral diversity misalignment.
- Alteration of phases due to ore dumps
- Alteration of phases associated with mine tunnel walls
- Mine water precipitates
- Minerals found in slag or the walls of smelters
- Minerals associated with mind dump fires
- Interaction with mine timbers or leaf litter
- Minerals associated with geothermal piping systems
Some of the minerals identified under those categories include:
- Schuetteite – Alteration phase recovered from ore dump. Found in an ocean mine dump in San Luis Obispo County, California.
- Hoganite – Interaction with mine timbers or leaf litter. Found in the Potosi mine in Broken Hill, Australia.
- Ferrarisite – Mine water precipitate. Found in Gabe Gottes mine in Alsace, France. This is a very old mine site, with its first discovery dating back to 1549.
- Hughesite – Alteration phase associated with mine tunnel walls. Found in the Sunday mine in San Miguel County, Colorado.
- Cuprospinel – Associated with mine dump fires. Found in the Consolidated Rambler mine in Newfoundland, Canada.
- Fiedlerite – Associated with slag. Found in an ancient mine slag heap in Lavrion, Greece.
Outside of mining-related phenomena, there was a small selection of minerals that arose from more unusual circumstances. Calclacite – Ca(CH3COO)Cl · 5H2O – was found to have formed in museum storage cabinets when acetic acid from the oak cabinet wood came in contact with calcareous rock and fossil specimens and pottery shards.
There was also Abhurite – Sn21Cl16(OH)14O6 – was associated with the alteration of tin archaeological artifacts in the wreck of the SS Cheerful, 14 miles NNW of St. Ives, Cornwall, England.
The paper also provided descriptions of more than 100 minerals that, although having known natural occurrences, were formed outside of their natural distributions due to human processes. While many of those out-of-place minerals were related to mining activities, seven were related to the alteration of lead, bronze, and tin artifacts, and four were discovered to have arisen due to the activities as sacrificial burning sites. Archaeology and cultural ritual as a driver of mineral diversity. Who knew?!
By unnaturally bringing substances in contact with each other, mankind is influencing mineralogical evolution in the same way it is influencing biologic evolution.
The authors also point out the profound influence that mankind is having on Earth’s geological record through the development of synthetic compounds which, by their very nature as ‘man-made’, are not classified as minerals. For instance, in their own words,
“Prior to human activities, the most significant ‘punctuation event’ in the diversity of crystalline compounds on Earth followed the Great Oxidation Event. Hazen et al. (2008) estimated that as many as two-thirds of Earth’s more than 5000 mineral species arose as a consequence of the biologically mediated rise of oxygen at ~2.4 to 2.2 Ga. By comparison, the production of the more than 180 000 inorganic crystalline compounds (as tabulated in the Inorganic Crystal Structure Database; http://icsd.fiz-karlsruhe.de) reflects a far more extensive and rapid punctuation event. Human ingenuity has led to a host of crystalline compounds that never before existed in the solar system, and perhaps in the universe. Thus, from a materials perspective (and in contrast to Earth’s vulnerable biodiversity), the Anthropocene Epoch is an era of unparalleled inorganic compound diversification.“
Like the authors, I wonder if these alterations will be enough to help advance that argument that we, as humanity, are creating a true Anthropocene Epoch – a distinct period with a lasting impression in the geologic record.
At the very least, the paper demonstrates the all-encompassing effect humans are having on the planet. Prior to this point, the dominant driver of biotic and abiotic diversity was the Earth itself and we are quickly pulling that responsibility from its grasp.
This post was updated from an earlier version published in 2017.
References and Further Reading
- Hazen, R. M., Grew, E. S., Origlieri, M. J., & Downs, R. T. (2017). On the mineralogy of the “Anthropocene Epoch”. American Mineralogist, 102(3), 595-611.