Telluric Iron Fathi Habashi

Telluric iron, also called native iron, is iron that originated on Earth, and is found in a metallic form rather than as an ore. Telluric iron is extremely rare, with only one known major deposit in the world, located in Greenland (Wikipedia).

Expeditions to Greenland In 1870 the Finnish-born Arctic explorer Adolf Erik Nordenskiöld (1832-1901) discovered large boulders of iron near Ovifak on the Disco Bay area of western Greenland (Figures 1, 2). He assumed that the metal was of meteoric origin. It seems however that this assumption was wrong since the boulders did not look like meteorites and that it would have been a strange coincidence that large meteorites would occur together in one place. The discovery was however documented on a Greenland stamp (Figures 3, 4) and the expedition was documented on other stamps (Figures 5-7).

Figure 1 - Disco Island in Greenland Figure 2 - Ovifak at the south west of Disco Island

Figure 3 - A Greenland stamp Fig. 4 - The original illustration which showing the iron boulders served as a basis for the stamp. discovered at Disco Island

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Figure 5 - Nordenskiöld on a Swedish stamp Figure 6.- Nordenskiöld on a Finnish stamp

Figure 7 - A Finnish stamp showing the ship Sofia used by Nordenskiöld in his 1883 expedition

Following his second expedition to Greenland in 1871, Nordenskiöld brought the iron boulder home for further study. An iron boulder weighing 22 metric tons was transported to Stockholm and placed outside the Swedish Museum of Natural History building (Figure 8 and 9). Three smaller boulders, a 6.6 ton block outside the Geological Museum in Copenhagen, and a 3-ton block can be found in Kaisaniemi Park in Helsinki (Figure 810 and one in Gothenburg.

Figure 8 - Moving the 22 tons iron boulder in Stockholm

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Figure 9 - A 22-tons iron boulder outside the Swedish Museum of Natural History in Stockholm

Figure 10 - A 3-tons iron boulder at Kaisaniemi Park in Helsinki

Nature of the iron boulders The Danish geologist Knud Johannes Vogelius Steenstrup (1842-1913) made nine journeys to Greenland. He accompanied Nordenskiöld in 1871 but disagreed with him about the origin of the boulders. Steenstrup found in ancient graves pieces of basalt containing round and irregular pieces of metallic iron. These pieces of iron he discovered were lying together with bone knives.

Steenstrup was able to show that the iron was of terrestrial origin. He thought that the boulders were formed when iron-rich basaltic lava reacted with underlying coal beds, creating such reducing conditions that native metallic iron segregated from the lava into massive nodules – a rare geological process. As the surrounding basalt eroded, the resistant iron nodules remained as loose boulders on the seashore at Ovifak.

Suggested Reading F. Habashi, Iron & Steel. History & Technology, Métallurgie Extractive Québec, Quebec City, 2016. Distributed by Laval University Bookstore, www.zone.ul.ca Laval University, Quebec City, Canada.

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