Introduction to Asbestos :

The name “asbestos” is used to refer to six kinds of mineral fibers having extensive commercial applications. These are naturally occurring fibers found in a majority of countries on almost every continent. They are normally categorized into two mineral groups, namely amphibole and serpentine.

The amphibole type is straight, needle-like, and contains five varieties of asbestiform including grunerite (amosite), actinolite, riebeckite (crocidolite), anthophyllite, and tremolite. The serpentine type usually has a curly shape and contains only one variety of asbestiform, namely chrysolite.

Over hundred mineral fibers are listed as asbestos-like fibers are listed with the U.S. Bureau of Mines, but only six aforementioned kinds are regulated by U. S. government. These very thin fibers can be separated, and are finer than human hair. These fibers can be seen with naked eyes. According to the Occupational Safety and Health Administration (OSHA), these fibers are at least 5 micrometers in length which is in actuality, three times the length of their diameters. For a better reference framework, mineralogists prefer working with fibers whose length is over thousand times the length of their diameters.

Kinds of Asbestos:

The six acknowledged silicate asbestos minerals include:

1. Amosite- (Also referred to as brown asbestos or as cummingtonite-grunerite) “Amosite” is its trade name, an acronym that stands for Asbestos Mines (after Amosa mines) of South Africa. These asbestos are in straight shape and quite brittle in their structure. Amosa asbestos are considered best if utilized for heat insulation.

2. Crocidolite- (Also referred to as blue asbestos or riebeckite) Made up of straight fibers and most of the crocidolite is obtained from Australia and southern Africa. It is considered the largest toxin form among all asbestos minerals.

3. Chrysotile- (Also referred as green or white asbestoa that gets its name from a Greek word which means ‘silky or fine hair’. It appears as whitish, curly fibers and comprises 95% of the total asbestos in use. Although this asbestos is mined all over the world, a major part of the U.S. demand is met from Africa, Canada, and previous Russia. It is considered as the least toxic among all asbestos in use.

4. Anthophyllite- This type of asbestos is white, brittle and holds different types of iron. It is found that it has tremendous resistance to heat and chemicals.

5. Actinolite- Typically elongated, with flat structure, and prismatic. In addition to asbestiform, actinolite is also found in other forms and is not so resistant to chemicals.

6. Tremolite- Rough in form, this asbestos appears chalky and whitish. Other than asbestiform, tremolite can be found in different mineral forms. It is being used as main ingredient in commercial and industrial talc.

Of these six types, chrysotile is the least complex and is used extensively for commercials products. Because of their construction, amphiboles, stay longer in lungs and may cause illness due to this reason. Some even believe that contaminations of these amphibole fibers within the chrysotile are the main cause of cancer deaths resulting from exposure to asbestos.