Zeolites from the Icelandic volcanoes
Volcanoes in Iceland have been a hot topic lately. If Katla joins in with Eyjafjallajokull (as it usually does within a year or so), then it could become rather hotter.
While it is hard to see the miles of black lava as a beautiful result, the extreme volcanic activity of Iceland does produce some exquisite surprises.
Zeolites are a group of complex silicate minerals that are famous for growing inside frozen air bubbles in lava. On Iceland, the endless movements of molten magma underground result in a lot of hot water being pumped through cracks in the rock. It is this water that holds the dissolved minerals from which the zeolites grow, and Iceland is probably the best place for them on the planet. This example from our collections is natrolite (Na2Al2Si3O10.2H2O) – a stunning specimen that was almost certainly collected in Iceland during the 19th century.
Zeolites are an important resource for a range of technological applications nowadays, mostly in chemistry. They have also been suggested as being vital to the origin of life. Volcanoes may cause some problems when they go off on your doorstep, but from a geological perspective that have all sorts of fascinating side-effects!