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ABsrp~cr: The dissolution of calcium carbonate with both organic and aqueous solvents was examined quantitatively and kinefically. Neither ethanol and nor acetone at 25°C dissolved appreciable aragonite or calcite, even after nearly ten days. Bleach (sodium hypochlorite) was a much less effective solvent than deionized water, producing little or no net calcium in solutions in contact with calcium carbonate. Although exposure to sodium hydroxide solutions also yielded relatively small concentrations of calcium in the fluid, characterization of the exposed carbonate grains by X-ray powder diffraction and by light microscopy revealed extensive replacement of the CaCO3 by Ca(OH)2, calcium hydroxide (portlandite). A solution of Aleonox@, a commercial laboratory anionic detergent, was about half again as potent as deionized water, and hydrogen peroxide proved to be many times more corrosive of calcium carbonate than deionized water.These results are consistent with published and anecdotal observations of the effects of laboratory preparation protocols on calcium carbonate. Our quantitative data permit the researcher to assess the potential for a treatment procedure using any of these solutions to compromise the integrity of a sample of calcium carbonate.

Maps showing anomalously high concentrations of 13 different elements in soils within the Mesa Quadrangle of southern Arizona were constructed using information contained in the National Uranium Resource Evaluation (NURE) database. Existing geochemical databases such as NURE provide an inexpensive and accessible resource that can be used to characterize an area geochemically. Anomalies in soils were determined after applying descriptive statistics, logarithmic transformations, elimination of outliers, and manipulation of below‐limit detection values. Among the elements with the most number of anomalies, Cu clustered in the southcentral part of the quadrangle where porphyry copper deposits are located, while As, Be, Co, Cr, Zn, Th, and U anomalies were located over exposed Precambrian and Tertiary igneous rocks. In general, anomalies could be related to the rocks cropping out, type of soils, and several mines present in the area.