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As part of a larger on-going research project, we found amphiboles in soils in Libby, Montana, that were derived from both the former vermiculite mine near Libby and other sources. SEM-EDS spectra of the soil amphiboles from these locations are used to ascertain if the amphiboles came from the vermiculite deposit near Libby, Montana, or some other source. This distinction is possible because amphiboles known to originate from the vermiculite deposit all contain Na and K that can be observed in the EDS spectra. We make this statement with confidence because multiple workers have performed EPMA characterization on over 40 amphiboles collected from the deposit and all are found to contain measureable amounts of Na and K. In this brief communication, we show examples from four locations that contain amphiboles consistent in composition and others that have inconsistent composition when compared to reference amphiboles collected from the vermiculite deposit. Also, we demonstrate the presence of amphiboles consistent in composition with amphiboles known to originate from the deposit in sediment that pre-date mining activity. A full-length publication is in preparation detailing the quantity, distribution, and composition of amphiboles in the Libby Valley, if they are consistent in composition with amphiboles known to originate from the deposit or not, and if they pre- or post-date mining operations. Keywords: Amphibole, amphibole asbestos, Libby, Montana, EPA, SEM-EDS

Five expanded vermiculite samples known to have originated from the former vermiculite mine near Libby, Montana were analyzed using powder XRD to quantify their amphibole content. An expanded vermiculite with no detectable amphibole based on our XRD methods discussed herein was spiked with 100, 500, 1000, 2500, 5000, 7500, and 10 000 ppm Libby amphiboles to determine the detection limit of XRD and to develop a calibration method. The 110 amphibole peaks were not detectable in the 100 and 500 ppm samples; thus, defining the detection limit. The 110 peak areas for the remaining samples were measured and used to form a calibration curve relating peak area to ppm amphibole. Of the five Libby samples, each had detectable levels of amphibole and their amphibole content ranged from 1171 to 9218 ppm. The XRD method provides a bulk measurement of the total amphibole content. To determine the amount of asbestiform amphiboles, morphological considerations obtained by microscopy techniques are required. From the results of a previous polarized light microscopy study, the five expanded vermiculites in this study would contain from 390 to 3073 ppm asbestiform amphiboles and not be subject to regulation on the basis of the 1% rule used by regulatory agencies in the U.S.A. Keywords: Amphibole, asbestos, powder X-ray diffraction, vermiculite

Extinction data sets for four centimeter-sized anisotropic crystals were collected in air with standard spindle-stage methods and submitted to a new Windows-based version of EXCALIBR, termed EXCALIBRW. EXCALIBRW solved these data sets with varying degrees of accuracy related to the external shape of the crystal: the more rounded the crystal, the more precise the results. For an olivine crystal ground into a sphere, the results were similar to those obtained for a crystal immersed in an index-matching fluid. However, even for samples bounded with growth or cleavage faces, the program determined the orientation of the optical indicatrix and 2V with an error of only 1-2[degrees]. Thus, this logical extension of spindle-stage methods is helpful: (1) to orient centimeter-size single crystals for various types of mineralogical measurements (e.g., spectroscopy or diffusion studies in which it might be undesirable to place the sample in a liquid); (2) as a non-destructive means of identifying gemstones based upon a determination of their optical class (i.e., isotropic vs. uniaxial vs. biaxial); and (3) for optical characterization by determination of 2V. In addition, the newest version of EXCALIBR is easier to use, mathematically more robust in its solution algorithms, and provides solutions for crystals in less favorable orientations than the earlier versions of EXCALIBR.