The design of contemporary solid fuel stoves and fireplaces incorporate not only stainless steel, glass, stones and ceramics but also more unusual materials. EuroFlames offers stoves and fireplaces in Cor-Ten finish. They claim that the lack of knowledge about this material leads to different version of how the typical rust-like surface is created. Some claim that the rusty coating is achieved by chemical treatment, others claim that the steel is left to rust and than sealed with “special coat of paint”. 
After a research, EuroFlames can share and clarify the Cor-ten origin. Cor-ten is a trademark of USS (US Steel Corporation) but this type of steel is also known as Atmofix produced in Europe, specifically in the Czech Republic. It is used mainly in construction and sculpturing. This low alloy steel protects itself from corrosion by forming a protective oxide patina. This oxide patina develops under conditions of alternating wetting and drying to produce a protective barrier, preventing the access of further moisture, oxygen and contaminants. The corrosion-like layer adheres to the base metal and is much less porous than the rust on the other metals. An important part in forming the corrosion on the surface plays the presence of low levels of copper, phosphorus, chrome and nickel.
The colour of Cor-ten varies over time and with exposure to different conditions. Initially, the material appears orange-brown as the protective layer begins to form. The steel than darkens within two to five years and reaches its typical dark brown, sometimes purple colouration.

Cor-Ten Light	Cor-Ten Dark

The texture is influenced by the orientation and the degree of shelter it is exposed to. Surfaces facing south and west develop smoother fine-grained texture. On the other hand, sheltered material facing north and east tend to develop a coarse granular texture.
Cor-ten has many benefits including high temperature resistance therefore used in stove construction, but also in flues, chimneys and ducting. Furthermore, it doesn’t need any surface treatment eliminating the need for paint and therefore making it eco-friendly.
The process of developing the Cor-ten makes the stoves or fireplaces constructed with this material more expensive but retailers should justify the cost with the long production process and the long-life benefits (such as durability and low maintenance).

Products in Cor-ten:

Caro XL	BIXBOX