What Is Anorthosite?
Anorthosite is a natural rock made almost entirely of plagioclase feldspar
— one of Earth’s most common minerals.
It holds aluminium, calcium and silica in near-perfect balance, giving it strength, brightness and chemical stability.
Unlike many industrial minerals, anorthosite is not a by-product.
It is a primary geological resource, formed more than 1.7 billion years ago when magma slowly cooled beneath what is now western Norway.
The result is a rock so pure and uniform that it can replace several raw materials in one clean source.
Gudvangen Anorthosite
Ca-rich Plagioclase (An80–95)
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Enduring Supply
Inside the mountain at Gudvangen lies an almost inexhaustible resource.
The massif contains hundreds of millions of tonnes of high-quality anorthosite, ensuring secure supply for generations of production.
Its proximity to the fjord allows direct access for shipping — short lines, low emissions and predictable logistics.
Norwegian Anorthosite is not just a material supplier but a long-term partner for modern industry.
Pure by Nature. Proven in Industry.
The Gudvangen deposit sits within the inner Sogn–Voss massif, one of Europe’s largest anorthosite bodies, covering more than 700 square kilometres.
Here, the rock is composed of over 90 percent plagioclase feldspar with exceptionally low levels of iron and titanium.
This purity gives the mineral its bright colour and stable chemistry.
It melts cleanly, reacts predictably and stays consistent from batch to batch.
This reliability has made it a preferred ingredient several industries.
Property | Typical Value | Role |
|---|---|---|
SiO₂ | ≈ 50 % | Network former |
Al₂O₃ | ≈ 30 % | Strength and viscosity |
CaO | ≈ 14 % | Flux and stabiliser |
Fe₂O₃ | < 0.5 %* | Low impurity, high brightness |
* After on-site magnetic separation.
Every grain of Gudvangen anorthosite is chemically stable and almost entirely plagioclase feldspar. It melts cleanly, bonds strongly and stays consistent — a natural material refined by geology, not by processing.
APPLICATIONS
From insulation to infrastructure — our anorthosite enhances material performance across industries. It helps manufacturers reduce additives, optimise energy use, and build stronger, longer-lasting products.
Fibreglass
Anorthosite supplies aluminium, calcium, and silica that melt efficiently, reducing energy use while improving fibre strength, durability, and manufacturing consistency
ASPHALT
Anorthosite can be specified as a high-durability asphalt aggregate, offering strong abrasion resistance, stable microtexture, and light surface reflectivity, with friction performance demonstrated through standard PSV and texture testing
Concrete
Anorthosite is suited to concrete because its stable aluminium–silica–calcium mineralogy enhances long-term durability, mix stability, and performance, with potential benefits in optimized, lower-cement formulations
Glass
Anorthosite contains aluminium, calcium, and silica that melt efficiently, reducing energy use while delivering consistent, high-quality glass.
CERAMICS
Anorthosite is feldspathic flux, promoting vitrification, lighter fired colour, controlled shrinkage, and consistent strength and surface finish in ceramic bodies and glazes
Stone Wool
Delivery of Al₂O₃ already bonded with SiO₂ and CaO. Lighter final product colour. Lower melting energy requirement. Stable and highly predictable mineralogy.
Performance Across Industries
APPLICATIONS
Performance Across Industries
From insulation to infrastructure — our anorthosite enhances material performance across industries. It helps manufacturers reduce additives, optimise energy use, and build stronger, longer-lasting products.
SUSTAINABILITY
Responsible by Nature
Every tonne is extracted with care for the mountain and the fjord. Closed water systems recycle process water, and the mine runs on renewable hydroelectric power. Transparent operations, low-emission transport and full traceability connect every shipment back to its origin.
Get in Touch
From Mountain Core to Modern Industry
Contact our team to learn how Gudvangen anorthosite can fit your process and support your sustainability goals.
