I am taking a online geology course for fun right now, the subject has always interested me and it is quite different from the maths heavy physics I am used to. Sweden has a grand history in geology, mineralogy and chemistry and chief among historic locations must be the mine in Ytterby, a suburb to Stockholm. In 1787 the lieutenant, chemist and amature geologist Carl Axel Arrhenius was sorting through the mine heap at Ytterby and discovered a unusually heavy black rock. Realizing that it must be a undiscovered mineral he sent samples of the rock to several chemists for analysis. The man that did the best job was Johan Gadolin and the mineral was named Gadolinite in his honor. The mineral contains, among other things, the element yttrium and it was the first of the rare earth elements to be discovered. Another 6 new elements where discovered in minerals from Ytterby and no less than 4 is named directly after the location (Yttrium, Terbium, Erbium and Ytterbium along with Skandium, Thulium and Holmium).
I happen to live in Stockholm which means a small field trip to Ytterby is a must and there I went a few weeks ago. Anyone that has been following the rare earth situation in China also knows that where there is rare earths usually one also finds Thorium, properly armed with a dosimeter I was looking forward to some rads! Continue reading Radioactive tourism - A trip to the Ytterby mine