geosciences Article A New Occurrence of Terrestrial Native Iron in the Earth’s Surface: The Ilia Thermogenic Travertine Case, Northwestern Euboea, Greece Christos Kanellopoulos 1,2,* ID , Eugenia Valsami-Jones 3,4, Panagiotis Voudouris 1, Christina Stouraiti 1 ID , Robert Moritz 2, Constantinos Mavrogonatos 1 ID and Panagiotis Mitropoulos 1,† 1 Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15784 Athens, Greece;
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[email protected] (P.M.) 2 Section of Earth and Environmental Sciences, University of Geneva, Rue des Maraichers 13, 1205 Geneva, Switzerland;
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[email protected] † Professor Panagiotis Mitropoulos has passed away in 2017. Received: 6 April 2018; Accepted: 23 July 2018; Published: 31 July 2018 Abstract: Native iron has been identified in an active thermogenic travertine deposit, located at Ilia area (Euboea Island, Greece). The deposit is forming around a hot spring, which is part of a large active metallogenetic hydrothermal system depositing ore-bearing travertines. The native iron occurs in two shapes: nodules with diameter 0.4 and 0.45 cm, and angular grains with length up to tens of µm. The travertine laminae around the spherical/ovoid nodules grow smoothly, and the angular grains are trapped inside the pores of the travertine.