Vals quartzite is a grey gneiss that can also tend towards greenish.
It is a stone rich in variations, layered, fine-grained and with light grey or white veins. It also contains large white eyes and layers of mica.
From a petrographic point of view, this stone is a gneiss despite its high quartz content. To be considered a quartzite, it would have to be composed almost exclusively of quartz.
This rock is particularly resistant to atmospheric agents and, to a lesser extent, to abrasion. We can therefore say that it is resistant to frost, acids and alkaline solutions.
Its composition is as follows: feldspar (albite/califeldspar), quartz, light mica (muscovite/fengite) and, in smaller percentages, dark mica (biotite), chlorite, sulphur minerals, titanite, garnet and epidote.
References for use of the material
Vals Thermal Baths, architect Peter Zumthor, Vals (Switzerland).
Main source of description
Material-Archiv. (2024). Valser Quarzit.
Original source of characteristic values
