The ARL SEMQ electron microprobe at the American Museum of Natural History (AMNH) was used to determine the composition of the starting materials. The feldspar used is labradorite and has a measured composition of An49.5Ab48.3Or2.2. Despite placing the labradorite through the magnetic separator, some foreign mineral phases were observed in the starting material, totaling less than 2%. The nature of these phases will be described in a later section. Pre- and post-experiment sands were examined using a Zeiss DSM 950 scanning electron microscope (SEM), also at AMNH. Two types of mounts were prepared for examination: loose grain mounts of the sand and polished sections. Loose grain mounts allow preservation of any fragile mineral growth and therefore provide textural information. Polished sections were used for quantitative analysis and characterization of 2-D spatial relationships.

Following each experiment, the fluid from each pore fluid intensifier was extracted and refrigerated for subsequent chemical analysis. Chemical analyses on the fluids were made using the Direct Current Plasma Spectrometer (DCP) at the Lamont-Doherty Earth Observatory. Major elements analyzed were Na, K, Ca, Si and Al. Fe and Ni were also analyzed to ensure that no significant dissolution of the Ni plating or stainless steel pore pressure tubing had occurred. In later analyses, K, Fe and Ni were not measured since earlier measurements indicated concentrations below detection limits. Solutions for chemical analysis were prepared by diluting 5 ml. aliquots of sampled solution with 45 ml. of 2 N trace element grade nitric acid. This was done primarily so that all dissolved species would remain in solution and also to preserve sampled fluid. Furthermore, dilution of the primary fluids resulted in concentrations that are well within the linear dynamic range of the DCP. Elemental concentrations were determined using three fluid standards which were prepared using SPEX standard solutions.

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