Asbestos refers to six naturally occurring fibrous minerals. These are: Amosite, Anthophyllite, Actinolite, Chrysotile, Crocidolite and Tremolite. The three most common of asbestos types found in the UK are as follows:
- Chrysotile (referred to as White asbestos).
- Amosite (referred to as Brown asbestos).
- Crocidolite (referred to as Blue asbestos).
Asbestos can be divided in to two groups Serpentine and Amphibole.
Chrysotile is the only asbestos fibre to be classed as a Serphintine mineral. The Serphintine fibres are curly and allow the Chrysotile fibres to be non-hydrophobic.
Amosite and Crocidolite are Amphibole minerals. Other fibres belonging to this group include: Actinolite, Anthophyllite and Tremolite are classed as “other fibres”. These minerals are hydrophobic this is because the fibres are needle like.
Asbestos has many physical properties that make it the perfect material in the world of industrial chemistry. Its tensile strength is far super to steal, its thermal stability and is thermal, chemical and electrical resistant.
Chrysotile has been used more than any other type and accounts for about 95% of the asbestos found in buildings in world. The most common use was corrugated asbestos cement roofing primarily for outbuildings, warehouses and garages. Chrysotile asbestos was also used in variety of other products for example: floor tiles, mastics, gaskets, adhesives, textured coatings, drainage goods, fire / heat retardant clothing, brake linings, electrical flash pads and pipe insulation just to name a few.
Amosite was mined in South Africa. It was mined because of its fire retardant / thermal insulation properties. Amosite was used in a variety of products, such as pipe insulation, insulating boards, and resin products such as toilet cisterns.
Crocidolite is found primarily in southern Africa, but also in Australia and Bolivia. Crocidolite is a blue mineral when in its parent rock. Crocidolite fibres are soft and very friable. Crocidolite was often mixed with other asbestos fibres. It was used in verity of products such as pipe insulation and asbestos cement.
Other regulated asbestos minerals, include:
- Tremolite asbestos.
- Actinolite asbestos.
- Anthophyllite asbestos.
These minerals were less commonly used industrially but can still be found in a variety of construction materials and insulation materials.