Amphibole content of cosmetic and pharmaceutical talcs.
The conditions that influenced the composition of heavy minerals varied for different layers of the Lemme section, which made some samples (layers) rich in minerals of higher density and others rich in lighter
amphibole (with a density of 3-3.5 g/[cm.sup.3]).
This is most likely due to a profound structural rearrangement in the process of metamorphic transformations, the formation of secondary minerals, such as micas and
amphiboles, which have low velocities in certain crystallographic directions, and weathering processes.
Comparative long-term toxicity of Libby
amphibole and amosite asbestos in rats after single or multiple intratracheal exposures.
We have determined in situ concentrations of 28 trace elements (REE, Ba, Rb, Sr, Th, U, Nb, Ta, Pb, Zr, Hf, Y, Sc, V, Co and Cr) in olivine, plagioclase, orthopyroxene, clinopyroxene,
amphibole and phlogopite on two polished thick sections (130 [micro]m) by laser ablation ICP-MS at the Natural History Museum of London, using a New Wave UP193FX gas laser source operating at 193 nm coupled to an Agilent 7500CS ICP-MS.
2A) comprising phenocrysts of plagioclase (30%),
amphibole (10%), quartz (15%), K-feldspar (10%), and biotite (3%) in a fine-grained matrix of the same minerals with accessory zircon, apatite, and sphene (Fig.
The minerals in these rocks consist of plagioclase,
amphibole and quartz that have granular textures and their plagioclase altered to sericite and epidotite (Fig 4C).
Amphibole fibers, as compared with chrysotile, are generally more toxic in part because
amphibole fibers accumulate more readily in the distal lung parenchyma, are not cleared as effectively, and are more durable.
Specifically, they are defined as being long and thin (having an aspect ratio greater than 3:1), and falling into categories of either "serpentine" (chrysotile) or "
amphibole" (tremolite, amosite, crocidolite, actinolite, and anthophyllite) [7].