PRELIMINARY - U.S. Geological Survey Certificate of Analysis
Material used in the preparation of AGV-2 was collected from the eastern side of Guano Valley, in Lake County, Oregon. This is the same location used to provide material for AGV-1. Information on the mineralogy and classification of AGV-2 is unavailable but it is assumed to be very similar to AGV-1 (Flanagan, 1967, 1969). Element concentrations for AGV-2 were obtained through a round robin study involving 23 international laboratories.
Element concentrations are recommended, if results from three of more independent laboratories using three or more independent analytical procedures are in statistical agreement. Information values with standard deviations are reported when three or more independent laboratories using at least two independent analytical procedures have provided information. Information values without standard deviations represent information from a single laboratory or analytical procedure. All isotopic information is from a single laboratory.
|Element||Wt %||±||Oxide||Wt %||±|
Dr. Geoff Plumlee
U.S. Geological Survey
Central Region Mineral Resources Team
Wilson, S.A., 1998, Data compilation and statistical analysis of intralaboratory results for AGV-2: U.S. Geological Survey Open-File Report (in progress).
|Wt %||Percent of total element concentration|
|µg/g||Total element concentration expressed as micrograms of element per gram of solid sample|
|±||One standard deviation|
|N||Number of labs reporting|
Order and Pricing Information
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USGS reference materials may be obtained directly from Dr. Stephen A. Wilson. The price for each reference material is listed in U.S. dollars and are subject to change. For domestic orders, this cost includes all shipping and handling charges using normal mail delivery by the U.S. Postal Service. For foreign orders, delivery charges will be added to the final bill. Urgent requests for reference materials should be initiated by Fax or e-mail. If required, expedited delivery is available with any additional shipping charges added to the final bill.
Dr. Stephen A. Wilson
U.S. Geological Survey
Box 25046, MS 964D
Denver, CO 80225
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