Period 4 element be dangerous in large enough quantities due to its radioactivity. Nickel (Ni) is an element in period 4, between cobalt and copper. Nickel is rare in the Earth's crust, mainly due to the fact that it reacts with oxygen in the air, with most of the nickel on Earth coming from nickel iron meteorites. However, nickel is incredibly common in the Earth's core; along with iron it is one of the two main components. Nickel is an important component of stainless steel, and in many superalloys. Copper (Cu) is an element in period 4, between nickel and zinc. Copper is
¡Cu-Cut! the team of editors and illustrators continued their work at Catalan children's magazine "En Patufet". On the occasion of the first centennial of the closure of the magazine, the Barcelona City Historical Archive ("Arxiu Històric de la Ciutat de Barcelona") staged an exhibition and published a catalogue based on the once famous magazine. The exhibition was commissioned by Catalan cartoonist Jaume Capdevila ("Kap") and produced with the "Associació Tantatinta". ¡Cu-Cut! ¡Cu-cut! was a Catalan illustrated satirical magazine, written in Catalan. Published in Barcelona between 1902 and 1912, it followed the political line marked by Francesc Cambó's Lliga Regionalista. ¡Cu-cut!, named