Edenite

Edenite is a calcium-bearing amphibole mineral closely related to tremolite, with extra sodium and aluminum in its crystal structure. It is best known in asbestos science as the parent of fluoro-edenite, the fluorine-rich fibrous amphibole linked to mesothelioma near Biancavilla, Sicily, and it also appears in small amounts among the Libby amphiboles.

Origin

Edenite is named after Edenville, in Orange County, New York, where it was first described. Fluoro-edenite, its fluorine-dominant form, was described as a new mineral from the volcanic rocks near Mount Etna around the turn of the twenty-first century.

Significance in Asbestos Context

Edenite itself is rarely the focus of a case, but its family shows why mineral names alone do not settle health questions. Fibrous fluoro-edenite was identified after researchers investigated unusually high rates of mesothelioma in Biancavilla, a town that used local quarry stone in construction, and IARC has since classified fluoro-edenite as carcinogenic to humans. Edenite compositions are also reported in some analyses of Libby, Montana vermiculite. Because edenite, tremolite and actinolite grade into one another chemically, a fiber near the boundary may be named differently by different labs. Like several other amphiboles, edenite is not on the short list of minerals named in most asbestos regulations, which can become a point of argument. When an edenite name appears in a report, the useful questions are whether the particles were asbestiform and how they were measured.

Example Sentence

The TEM analysis identified a few amphibole fibers with edenite-range chemistry alongside the more common tremolite.

Related Terms

fluoro-edenite, Biancavilla, Calcic Amphibole, Tremolite, amphibole nomenclature, Libby amphiboles, IARC Classification

Notes

• An unfamiliar amphibole name in a report is worth asking an expert about; it may be closely related to regulated asbestos.
• Ask whether the identification was based on chemistry, crystal structure, or both.