In 1890, the natural stone industry in Switzerland experienced an enormous expansion. With the arrival of concrete and artificial stones for construction, in 1900 a continual downsizing of the natural stone sector began which is lasting until today. Between 1915 and 1965, the number of operating quarries decreased by two thirds, caused not only by the introduction of artificial stones but also by the decreased demand for certain natural stone materials such as blackboards, whetstones, mortars and lithographic stones. On the other hand, the extraction of intact rocks for the fabrication of crushed hard rock products such as gravel or ballast as well as raw materials for the binding material industry (cement and concrete industries) increased.

The quarries shown are subdivided in eleven groups according to rock type:

Sandstone
Intact rock/sediments, composed primarily from components with grain size between 0.2 and 2 mm.

Conglomerate/Breccia
Intact rock/sediments, principally formed of components with grain size larger than 8 mm. While breccias have angular components, those of conglomerates are of a rounded shape (e.g. Nagelfluh).

Roofing slate
In Alpine regions, flat slate rocks are used as roof material. The most important slate deposits in the Alps are located in areas with weak metamorphic, limestone-clayey sediments. Flysch slate (Glarnus slate, Niesen slate) and the Mesozoic roofing slate from the canton of Wallis are the most significant.

Limestone
The term limestone (often shortened to lime) refers to rocks which contain, in addition to calcite, less than 20% of clay minerals and iron oxide. Their content in non-carbonate components must not exceed 40%. Marble is a limestone transformed and recrystallized during orogenesis.

Tufa
Tufa is a is a porous and terrestrial sedimentary rock, formed by the precipitation of carbonate minerals from solution in ground and surface waters.

Marl
Marl contains variable amounts of clays and silt. Marl was originally an old term loosely applied to a variety of materials, most of which occur as loose, earthy deposits consisting chiefly of an intimate mixture of clay and calcium carbonate, specifically an earthy substance containing 35–65% clay and 65–35% carbonate.

Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate.

Granite/Diorite/Quartzite porphyries
Magmatic rocks (plutonite). Granites are light coloured, coarsely grained rocks which are composed of quartz, feldspar and mica. Quartzite porphyries contain a sometimes glassy matrix with scattered quartz or feldspar crystals.

Gneiss
Coarsely folded, grainy, metamorphic rocks (centimetre or decimetre scale thick plates); primarily composed of feldspar, quartz and mica.

Micaschists
Easily splitted metamorphic rocks (millimetre to centimetre scale thick plates); primarily formed of finely foliated, squamous (e.g. mica) or needle-shaped (e.g. amphibole) minerals.

Serpentinite/Talc-/Chloritic schists
Metamorphic rocks with a low silica content (less than 45%) and less than 10% lightly coloured components.

The rock types extracted from the various locations are directly correlated to the geological structure of our country. The rocks extracted from the Jura, the Plateau and the Alps thus exhibit some typical characteristics.

The Jura provides, with the exception of Keuper sandstone, relatively compact limestone primarily ranging in colour from beige and yellow to light red and more seldom light grey or virtually white. They are hard, tend to fracture or flake under the effect of weathering but if correctly used can last for many centuries.

On the Plateau, primarily sandstone, and to a lesser extent shell limestone, are extracted for construction stones. In addition, granitic sandstone or upper fresh water molasse are of special value. Otherwise, local conglomerates (Nagelfluh) are extracted.

The Alps, corresponding to their geological diversity, are the repository for natural stones. In the northern sediment layers, primarily limestone, flysch sandstone and some verrucano are found. From the central massifs originate granites, gneiss and some specialities such as serpentinite and soapstone. The Pennine layers offer a large selection of rocks: gneiss in many colourful varieties; light to heavily marked marble; dark green-black serpentine and green schists (prasinite). The southern Alps contribute to the diversity of Alpine specimens, with the colourful Lias limestone from Arzo with a pronounced breccia-type structure.