Gneiss

Listed in our range under Granite.

Andeer

Andeer is one of the most tradition-rich Swiss building stones — a directionally foliated augen gneiss from the quarrying district near the village of Andeer in the Viamala Gorge in Graubünden, in the Swiss Alps. It has a characteristic green-grey groundmass with subtle green shimmering reflections (from chlorite and epidote) and pale white plagioclase and quartz “eyes” in the manner of the classic augen gneiss structure. Also traded internationally as Verde Andeer, Alpina and Rofna gneiss; used for external facades, paving, external stairs, terrace slabs, floor areas, building applications with an Alpine character and heritage restoration work in the Swiss dimension-stone tradition.

Andeer ist petrographisch ein Gneis (DNSA Stein 41 und 3666) — ein gerichtet folierter metamorpher Hartstein mit Augen-Struktur. Im internationalen Handel wird der Stein traditionell als 'Granit' geführt, weil er in Verarbeitung und mechanischen Eigenschaften wie ein klassischer Hartstein gehandhabt wird. Bei ROSSITTIS klassifizieren wir Andeer handelsüblich in der Granit-Familie gemäß weit verbreiteter Trade-Konvention für alpine Gneise.

Gneiss Switzerland 2.670 kg/m³

Available as: Slabs, Paving slabs, Tiles and flooring slabs, Crust slabs · 3 of 61 reserved

Check the live stock Request an appointment

About Andeer

Andeer shows an exceptionally characterful Alpine gneiss appearance with a distinctively Swiss green cast. The groundmass is a green-grey to grey-green matrix with subtle green shimmering reflections produced by embedded chlorite and epidote minerals — this green tone is the defining element that gives the stone its name, which is why it is also traded as “Verde Andeer” (Italian: “green Andeer”). Pale whitish plagioclase and quartz crystals are distributed across the whole slab in egg-shaped to elongated “eye” structures — a characteristic augen gneiss fabric in which individual feldspar crystals were plastically deformed during metamorphism and squeezed out into oval forms. The mineral fabric is directionally foliated (layered, that is, oriented along one direction) — typical of metamorphic gneisses. The finishes currently available from stock are listed in the »Finishes« block further down this page.

Geologically, Andeer is a Precambrian to Palaeozoic gneiss from the Alpine Swiss granite/gneiss complex of the Adula nappe. The quarries lie in the Andeer region in the Viamala Gorge in Graubünden, in the south of Switzerland close to the Italian border. The region has been known as a dimension-stone province for centuries — Andeer gneiss was already being used for Swiss buildings in the Middle Ages and in Roman antiquity. Petrographically it is a well-foliated gneiss with characteristic augen structures — comparable to the Italian Serizzo Monte Rosa from the Ossola valley. The DNSA dimension-stone records list the material under two entries (stone 41 and 3666 — both for the same stone). Several synonyms circulate in international trade: Verde Andeer (the Italian spelling variant — the widely used Italian trade name), Alpina, Rofna gneiss (after the neighbouring Rofna valley area), Andeer Gneis and Swiss Green Gneiss. The augen gneiss fabric and the greenish tone point to a shared metamorphic history with the Italian Beola and Serizzo gneisses of the Alps.

Technically, Andeer shows exceptionally strong values: bulk density 2,670 kg/m³, compressive strength 190–220 MPa (very high), flexural strength an exceptional 23.4 MPa (well above typical granite values — characteristic of a well-foliated augen gneiss), water absorption 0.37 % (low), Mohs hardness 6–7. Full frost and acid resistance is confirmed for this silicate rock — wine, lemon juice, vinegar or bathroom cleaners leave no etch marks as they would on marble or limestone. The high flexural strength qualifies the stone for demanding paving carrying heavy traffic. Its proven performance on Swiss buildings over centuries confirms the long-term weathering stability under Alpine climatic conditions.

ROSSITTIS carries Andeer as a raw slab in 10, 20, 30 and 40 mm thicknesses (standard thicknesses plus solid applications for stairs or paving), as tiles for floor and wall applications, as treads and risers, as terrace slabs and for project-specific cutting. The finishes currently available from stock are listed in the »Finishes« block further down this page.

Compared with other Alpine gneisses, Andeer is a Swiss choice with deep tradition: Serizzo Monte Rosa (an Italian Beola gneiss from the Ossola valley with a similar augen structure) is a more neutral grey without the green cast; Verde Salvan (another Swiss green gneiss) is closely related; Calanca gneiss (a Ticino gneiss) shares the same Alpine dimension-stone tradition; Vals quartzite (Graubünden, Vals) is a different type of dimension stone. Within the Swiss dimension-stone tradition, Andeer is among the most widely used and best-proven selections — the stone has been used for centuries for Swiss buildings, paving, external stairs and heritage restoration work. For architectural projects with an Alpine, traditional or Swiss character — external facades on Alpine buildings, heritage restoration of historic Swiss structures, paving in Swiss town centres, external stairs carrying heavy traffic and building applications with a green natural stone accent — Andeer is a choice with deep tradition and dependable planning within the classic Swiss gneiss range.

Technical data

Guide values for the stone type, taken from manufacturer and test reports. Natural stone is a natural product — individual batches and slabs can differ. For critical applications, request slab-specific test data.

Rohdichte 2.670 kg/m³

Druckfestigkeit 205,0 MPa

Biegezugfestigkeit 23,4 MPa

Wasseraufnahme 0,37 %

Finishes

Andeer is available in a range of finishes. The finish affects appearance, feel and the care it needs.

Poliert

Politur ist die klassischste Veredelung im Hartgesteinsegment — eine spiegelglatte, hochglänzende Oberfläche mit höchstmöglicher Farbintensität und maximaler Tiefenwirkung der Mineralstruktur. Als säurebeständiges Silikatgestein ist polierter Granit pflegeleicht und für Küchenarbeitsplatten, Wandverkleidungen und repräsentative Sichtflächen erste Wahl.

Geschliffen C120

Mattes Erscheinungsbild durch groben Schliff mit Körnung C120 — die ebene Oberfläche zeigt eine zurückhaltendere Farbintensität als poliert und kann sichtbare Schleifspuren tragen. Im Vergleich zur Politur pflegeintensiver, aber stilistisch ruhiger; bevorzugte Wahl für moderne Innenarchitektur mit reduzierter Reflexion.

Geflammt + 1 x gebürstet

Die Oberfläche wird durch Hitze aufgeraut und einmal gebürstet, um scharfkantige Mineralreste zu glätten und loses Material zu entfernen. Etwas sanftere Haptik als rein geflammt, weiterhin rutschhemmend, Farbe weniger intensiv als poliert. Standardwahl für Außenbereiche, Terrassen und stark beanspruchte Bodenflächen.

Care & fabrication

As a Swiss Alpine gneiss, Andeer is a robust hard rock with low water absorption (0.37 %), full frost and acid resistance and exceptionally high flexural strength. Wine, lemon juice, vinegar, cola, bathroom cleaners or descalers leave no etch marks as they would on marble or limestone — the stone is markedly easier to look after and is ideally suited to intensive everyday use.

For internal applications we recommend sealing on a silane or polysiloxane basis at first installation. On polished surfaces, refreshing the sealer every 8–10 years is sufficient; on heavily used floor areas or external applications, check it every 3–5 years.

Routine care is with a pH-neutral natural stone cleaner and a soft cloth or microfibre mop. Clear warm water is usually sufficient. Acidic cleaners are not in themselves a problem, but should nevertheless be avoided because they can attack the sealer. Outdoors, dirt, moss and de-icing salt residues should be removed regularly — if neglected for long periods, the foliated mineral fabric can hold dirt or moss in its fine mica lines.

For external applications Andeer is outstandingly suited — the stone has proved its exceptional weathering stability under Alpine climatic conditions on Swiss buildings over centuries. The high flexural strength (23.4 MPa) qualifies it particularly for heavily loaded paving and building applications. The finishes currently available from stock are listed in the »Finishes« block further down this page.

For paving, Andeer is a Swiss choice with deep tradition — its high compressive strength, flexural strength and excellent frost resistance qualify the stone for heavily loaded town-centre paving, Alpine building applications, kerbs and squares. For paving carrying vehicle traffic we recommend slab thicknesses of at least 30–40 mm.

For pool surrounds, external terraces and fountain surrounds, a slip-resistant textured finish is mandatory — polished external surfaces present a high risk of slipping when wet. In areas with frequent salt contact we recommend refreshing the sealer every 3 years. As an Alpine dimension stone proven through centuries of Swiss winters, Andeer is particularly tolerant of road salt.

Frequently asked questions

What is Andeer geologically?

Andeer is a Precambrian to Palaeozoic Alpine gneiss from the Swiss granite/gneiss complex of the Adula nappe. The quarries lie in the Andeer region in the Viamala Gorge in Graubünden, in the south of Switzerland close to the Italian border. Petrographically it is a well-foliated gneiss with characteristic augen structures of white plagioclase and quartz crystals. The green tone comes from embedded chlorite and epidote minerals. The DNSA lists the material under two entries (stone 41 and 3666).

What synonyms are there?

In international trade, Andeer also runs under the designations Verde Andeer (the Italian spelling variant — the widely used Italian trade name meaning “green Andeer”), Alpina, Rofna gneiss (after the neighbouring Rofna valley area), Andeer Gneis and Swiss Green Gneiss. All of these designations refer to the same Swiss augen gneiss from the Andeer quarrying district.

What technical values does Andeer have?

Exceptionally strong values: bulk density 2,670 kg/m³, compressive strength 190–220 MPa (very high), flexural strength an exceptional 23.4 MPa (well above typical granite values — characteristic of a well-foliated augen gneiss), water absorption 0.37 %, Mohs hardness 6–7. Full frost and acid resistance is confirmed for this silicate rock. These values qualify Andeer fully for demanding Alpine external applications exposed to frost and de-icing salt.

What are the white eyes in Andeer?

The pale white “eyes” in Andeer are egg-shaped to elongated domains of plagioclase and quartz crystals formed during metamorphism. Under tectonic compression, individual feldspar crystals from the original granite protolith were plastically deformed and squeezed out into oval forms within the green-grey matrix. This augen gneiss fabric gives rise to the Italian term “Ghiandonata” (with eyes) and is characteristic of Alpine gneisses from Switzerland and northern Italy.

Andeer or Serizzo Monte Rosa?

Both are Alpine augen gneisses from the Swiss-Italian Alpine complex and have similar petrographic properties. Serizzo Monte Rosa (Italian, from the Ossola valley in Piedmont) is a more neutral silvery grey without the green cast — the classic Italian variant. Andeer (Swiss, Graubünden) has characteristic green shimmering reflections and is regarded as the typical Swiss variant within the Alpine dimension-stone tradition. Both are suitable for similar applications; the choice is primarily an aesthetic one between neutral grey (Serizzo) and green (Andeer).

Is Andeer suitable for paving?

Outstandingly so — and this is one of its most important traditional applications. The high compressive strength (190–220 MPa), the exceptional flexural strength (23.4 MPa) and the excellent frost resistance qualify the stone for heavily loaded town-centre paving, Alpine building applications, kerbs and squares. Andeer has been used in Switzerland for classic paving applications for centuries — its performance under Alpine climatic conditions has been proven across generations. For paving carrying vehicle traffic we recommend slab thicknesses of at least 30–40 mm.

What finishes are available in Andeer?

The finishes currently available from stock are listed in the »Finishes« block on this page.

Is Andeer suitable for heritage restoration work?

Outstandingly so — and this is one of its traditional principal applications. Andeer has been used for centuries for Swiss buildings, paving and external stairs. For the restoration of historic Swiss structures, heritage conservation work and the Alpine dimension-stone tradition, Andeer is the authentic choice, with the material authenticity required and long-term weathering stability under Alpine climatic conditions.