Contain meteorites gold

Space mining raw materials from the cosmos - Potsdam geoscientists examine meteorites found 200 years ago

Meteorites are not one of the geohazards that we think about a lot. Still, these extraterrestrial visitors play an important role. Scientists today are even discussing whether life on earth was made possible in the first place by meteorites. For example, there are many indications that the water, which is essential for us and every other life on our planet, comes from meteorites.

Around 22,000 larger meteorite fragments have been found on Earth so far. 45 such "extraterrestrials" even in Germany. But only very few of them - the fastest and heaviest - have blasted an impact crater into the earth's crust. Some of the fragments weigh only a few grams, other fragments weigh up to 60,000 kilograms - like the Hoba meteorite in Namibia. In total, around 40,000 tons of extraterrestrial material pelt down the earth every year.

Around once a month bright luminous phenomena can be observed in the sky somewhere in the world. Most of the time, meteors burn up completely in the atmosphere. But time and again small fragments hit the surface of the earth. When this happens, they are called meteorites. Since almost 75 percent of the earth's surface is covered with water, most of the fragments lie on the bottom of the oceans. The few that hit the land quickly weather thanks to wind and weather and are therefore never found. In the eternal ice of the poles and in the driest deserts on earth, there is the greatest chance of finding a meteorite, because there is hardly any weathering here.

200 year old meteorite was analyzed in Potsdam

A research team from Potsdam has now taken a closer look at such a meteorite, the Santa Rosa de Viterbo meteorite from Colombia, which was discovered in 1810. The scientists around apl. With their analyzes, Uwe Altenberger would like to find new and valuable information on the formation of our solar system. Since the cosmic travelers come partly from the cores of old stars, the mineralogists and geochemists can use their analysis to find out which chemical elements have determined the structure of stars for billions of years.

The Santa Rosa de Viterbo meteorite belongs to the class of so-called iron-nickel meteorites. As a rule, these contain metals and metallic compounds, which are now also viewed as potential deposits due to the increasing scarcity of raw materials. Rare metals such as germanium, palladium and iridium have already been detected in meteorites. Uwe Altenberger and Barbara Bsdok from the UP Institute for Geosciences, Prof. Ana Concha from the Universidad Nacional in Bogota and Dr. Franziska Wilke from the GeoForschungsZentrum Potsdam have now been able to detect a very high concentration of gold in the Santa Rosa de Viterbo meteorite from Colombia. In their recently published study, they show that the Getseinsbrocken with a gold content of around 400 grams per ton is the gold-richest iron-nickel meteorite that has ever been described. In comparison, a concentration of 3 to 5 grams per ton, at which earth's rock is extracted in mines, seems downright sparse. To what extent the mining of near-Earth asteroids could really become economical remains to be seen; There are already numerous industrial initiatives.

Publication:
B. Bsdok, U. Altenberger, A.. Concha-Perdomo, F. D. H. Wilke, J. G. Gil-Rodríguez. The Santa Rosa de Viterbo meteorite, Colombia. New work on it's petrological, geochemical and economical characterization. Journal of South American Earth Sciences. Volume 104 December 2020. DOI: 10.1016 / j.jsames.2020.102779