Magic White Caves of Gudvangen

Magical White Caves

Useful Information

Location:	Gudvangen. 8.2 km from the Gudvangen ferry quay, E16 road to Voss. (60.844114, 6.726850)
Open:	MAY to SEP daily for groups after appointment. [2021]
Fee:
Classification:	Rock Mine
Light:	Incandescent Electric Light System Son et Lumière
Dimension:	T=8 °C.
Guided tours:	D=45 min, Min=20.
Photography:
Accessibility:
Bibliography:	Jan Egil Wanvik (2000): Norwegian anorthosites and their industrial uses, with emphasis on the massifs of the Inner Sogn-Voss area in western Norway, NGU-Bull 436, 2000 - page 103ff. researchagte
Address:	Magic White Caves of Gudvangen, Gudvangen Fjordtell, 5747 Gudvangen, Tel: +47-480-75-555. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

Geology

In Gudvangen is said to be the world’s largest deposit of anorthosite. Anorthosite is a phaneritic, intrusive igneous rock characterized by its composition: mostly plagioclase feldspar (90–100%), with a minimal mafic component (0–10%). The mafic minerals are normally pyroxene, ilmenite, magnetite, and olivine.

So many mineralogical terms require some explanations. A phanerite is an igneous rock whose microstructure is made up of crystals large enough to be distinguished with the unaided eye. If the crystals are too small to be seen with the naked eye the rock is called aphanitic. So anorthosite was formed by the intrusion of magma into the crust which cools rather slow, so crystals have time to form during the cooling process. Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron.

Anorthosites are a topic of geologic research, because it is not fully understood how they form. And there are different kinds of anorthosites which are Archean-age anorthosites, Proterozoic anorthosite, layered intrusions, mid-ocean ridge and transform fault anorthosites, and finally anorthosite xenoliths in other rocks like granites, kimberlites, or basalts. There are also big deposits of anorthosites on the moon, which constitute the light-coloured areas and have been the subject of much research.

The deposit of the Nreifjord belongs to the Voss-Sogn anorthosite massiv is a high aluminium variety which makes it attractive for a variety of industrial end uses. The webpages which state that it is a sort of marble are wrong, its and intrusive rock composed of feldspar, not a metamorphic rock composed of limestone. The rock actually contains aluminium and gold as stated, but that's a truism, most rocks contain those elements in traces, and the anorthosite is not an ore with profitable amounts of each. It was actually mined to create gravel for roads, add it to concrete, or similar purposes. And while the deposit is one of the biggest in Norway and even Europe, it is definitely far from being the biggest of the World. These are false facts told to tourists, and if you think about it, they are irrelevant anyway.

Description

The Magic White Caves near Gudvangen are one of the most popular tourist venues at the town. This is a former underground quarry where the famous white anorthosite was quarried. The deposit on the side of the Nreifjord forms a steep cliff which is called Mount Anorthosit. The white rock was used for many purposes in the area.

The result of the mining are underground chambers and passages, mostly rectangular and quite spacious, which are now used for various purposes. They are a sort of local event location, used for functions, concerts, and other events. There is a stone bar and a dining hall which seats 300 on reindeer skin covered benches.

There are also underground tours available, but they are mostly based on fantasy stories and a son et lumière lightshow, which uses the white rock as a canvas for light art and laser shows. There are neither geologic nor historic explanations on the tour, which is a bit unsatisfactory. Many visitors are disappointed, the comments of travel portals are One installation resembles the polar light. Obviously quite popular during summer, when it is impossible to see the polar light because the days last 20 hours and the nights are more like dawn. Completely uninteresting during winter, when polar lights can be seen almost every night for 12 hours at least.

The tours into the mine are offered for groups only. There are no regular open hours or tours for individuals. Visitors are equipped with jackets and helmets, more for show than anything else. Jacket and helmet are not required for events.

Underground mining of white anorthosite began in Nærøydal In the mid 1960s. Products include white road aggregate, white concrete aggregate, and abrasives for use in toothpaste and cleaning agents.