The enormous crystal group hewn out of the rock on the Planggenstock above the Göscheneralpsee in 2006, is on show, together with quite a few other large crystals, in the old Church in Flüelen, very near the railway station. The entrance fee Fr.10.00 includes use of the tape (five languages) so one can go round the exhibits as quickly or as slowly as one likes. Upstairs is a film showing more details of getting the crystal out of the rock. A booklet is also available in English Fr.5.00.
As the exhibition is really quite small, it is not the sort of thing one would decide to go a long distance to visit, but if one is in the area around of Lake Lucerne, it would be a great opportunity to see something quite special. We went in after a hike and it was well worth the short detour. It is a wonderful thought that the two men who found this enormous crystal after so many years work in the rock wanted it to be displayed in the canton in which it was found, allowing the general public to see it, rather than selling it abroad.

If you're into rock crystals, then maybe check out the crystal cave at the Grimsel Test Site, at Gerstenegg. Never been there myself. It might be getting a bit late in the season though...

It is only a small exhibition but we found it really interesting, my son loves Geology and he was suitably impressed. As mentioned it would be worth visiting as part of a group of activities in the area. Hiking up Eggberg is good, Tell museum in Burglen is very interesting as is the Tell Trail from Burglen to Altdorf (30 min stroll telling the story on info boards at regular intervals). Rounded off by a nice meal in one of the many restaurants, I would recommend Pizzaria Da Sergio in Moosbad, Pouletburg in Attinghausen or Schutzenstube in Fluelen dorf. There you go a nice Family Sunday day out.