Asbestos is the commercial term for a group of six fibrous silicates (Chemical Abstract Service or CAS classification) which includes: chrysotile ; asbestiform tremolite, asbestiform actinolite, asbestiform anthophillite, amosite and crocidolite of the amphibole groups. Maps showing the asbestos distribution in France with a focus on the French Alps have been published by the BRGM (Dessandier & Spencer, 2005; Lahondère et al., 2001, 2012 and Lahondère et al., 2012, 2013). These authors classified the “asbestos prevalence” using 5 levels of intensity, whereby 0 means an asbestos free area, to level 4 where asbestos has been identified and represents an environmental hazard. There are 9 level 4 asbestos occurrences in the alpine Corsica, including the defunct Canari Mine (closed in 1965); and 7 more occurrences in the western Alps, including the Termignon, Lanslebourg, Bessans and Val de Peas areas. The Chamrousse ophiolitic complex in Beledonne massif, in which tremolite and actinolite fibers associated with serpentinized peridotites (Lahondere et al., 2013) has been observed is also classified level 4. Chrysotile is the most common asbestiform mineral observed at those locations. It is commonly associated to serpentinized peridotites that commonly form part of ophiolite complexes. It is characterized by long and flexible fibers and easily recognizable using Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) coupled to EDS. Tremolite and actinolite fibers are often, but not necessarily, associated with chrysotile. Tremolite and actinolite fibers could be of an asbestiform type or a non-asbestiform type depending of their morphology and their specific crystallographic properties. Asbestiform tremolite and actinolite must have high L/D properties (L/D > 20), been less than 3 μm in diameter and measure less than 25μm. In addition, they should not be fragments of lager crystals as they have to be the results of grown fibers under hydrothermal conditions. Tremolite and actinolite fiber detection requires the use of a SEM coupled to EDS and often need to be complemented with observations under TEM for diffraction patterns which differentiate fibers from an asbestiform type to a non-asbestiform tremolite and actinolite type.