PRELIMINARY - U.S. Geological Survey Certificate of Analysis

Andesite, AGV-2

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.

Recommended Values | Information Values | Certificate Information | Bibliography | Glossary | Order and Pricing Information


Element Wt % ± Oxide Wt % ±
Al 8.95 0.11 Al2O3 16.91 0.21
Ca 3.72 0.09 CaO 5.20 0.13
Fe 4.68 0.09 Fe2O3 6.69 0.13
K 2.39 0.09 K2O 2.88 0.11
Mg 1.08 0.02 MgO 1.79 0.03
Na 3.11 0.09 Na2O 4.19 0.13
P 0.21 0.01 P2O5 0.48 0.02
Si 27.7 0.35 SiO2 59.3 0.7
Ti 0.63 0.13 TiO2 1.05 0.22
Element µg/g ± Element µg/g ±
Ba 1140 32 Pb 13 1
Be 2.3 0.4 Pr 8.3 0.6
Ce 68 3 Rb 68.6 2.3
Co 16 1 Sc 13 1
Cr 17 2 Sr 658 17
Cu 53 4 Th 6.1 0.6
Dy 3.6 0.2 U 1.88 0.16
Ga 20 1 V 120 5
La 38 1 Y 20 1
Mn 770 20 Yb 1.6 0.2
Nb 15 1 Zn 86 8
Nd 30 2 Zr 230 4
Ni 19 3

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Information Values

Element µg/g ± Element µg/g ±
Cs 1.16 0.08 Lu 0.25 0.01
Er 1.79 0.11 Sb 0.6  
Eu 1.54 0.10 Sm 5.7 0.3
F 440   Sn 2.3 0.4
Gd 4.69 0.26 Ta 0.89 0.08
Hf 5.08 0.20 Tb 0.64 0.04
Ho 0.71 0.08 Tl 0.27  
Li 11   Tm 0.26 0.02
Element Isotopic Ratios ± N
Pb 206/204 18.864 0.007 1
Pb 207/204 15.609 0.006 1
Pb 208/204 38.511 0.020 1

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Certificate Information

Issued 4-30-98
Denver, Colorado

Dr. Geoff Plumlee
U.S. Geological Survey
Central Region Mineral Resources Team

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Bibliography

Wilson, S.A., 1998, Data compilation and statistical analysis of intralaboratory results for AGV-2: U.S. Geological Survey Open-File Report (in progress).

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Glossary

Symbol Definition
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

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Order and Pricing Information

Placing an Order

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.

To order a USGS Reference Material, please contact Dr. Stephen Wilson or use the downloadable form: Order Form (Word) (22 KB) or Order Form (PDF) (238 KB).

Dr. Stephen A. Wilson
U.S. Geological Survey
Box 25046, MS 964D
Denver, CO 80225
Tel: 303-236-2454
FAX: 303-236-3200 or 303-236-1425
Email: (swilson@usgs.gov)

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Payments for domestic or international orders using a credit card receive a 10% discount on the per bottle price.

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Please download the agreement form and follow the instructions on the form when placing your order.

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