USGS Certificate of Analysis Mica Schist, SDC-1 (Geochemical Reference Standards)

Material used in the preparation of this standard was collected in 1963 from the Washington D.C. area. The material is probably of late Precambrian age, and examination of hand specimens reveals a dark gray pervasively foliated muscovite-quartz schist with a homogeneous thinly streaked texture (Flanagan, 1976).

Element concentrations were determined by cooperating laboratories using a variety of analytical methods. Certificate values are based primarily on international data compilations (Abbey, 1983, Gladney and Roelandts, 1988, Govindaraju, 1994). Initial USGS studies (Flanagan, 1976) provide limited background information on this reference material.

Recommended Values

Oxide	Wt %	±	Oxide	Wt %	±
SiO₂	65.8	0.43	Na₂O	2.05	0.09
Al₂O₃	15.8	0.34	K₂O	3.28	0.10
Fe₂O₃	2.62	0.15	TiO₂	1.01	0.04
FeO	3.93	0.15	CaO	1.40	0.07
Fe₂O₃T	6.32	0.23	MgO	1.69	0.10
			P₂O₅	0.16	0.025

Element	µg/g	±	Element	µg/g	±	Element	µg/g	±
As	0.22	0.01	Ga	21	1.4	Sc	17	2
Ba	630	60	Gd	7	0.4	Sm	8.2	0.5
Be	3	0.5	Hf	8.3	0.2	Sn	3.0	0.2
Ce	93	7	La	42	3	Sr	180	9
Co	18	1	Li	34	3	Th	12	0.9
Cr	64	7	Mn	880	60	U	3.1	0.2
Cs	4	0.2	Nd	40	4	V	102	12
Cu	30	3	Pb	25	2	Zn	103	8
F	600	30	Rb	127	7	Zr	290	30
			Sb	0.54	0.05

Element	µg/g	Element	µg/g	Element	µg/g
B	13	Hg	0.2	Tb	1.2
Cl	32	Ho	1.5	Tl	0.7
Dy	6.7	Nb	21	Tm	0.65
Er	4.1	Ni	38	W	0.80
Eu	1.7	Ta	1.2	Yb	4

Return to top of page

Certificate Information

Denver, Colorado
revised March 1995

David B. Smith
Central Region Mineral Resources Team (formerly Branch of Geochemistry)

Return to top of page

Bibliography

Abbey, S., 1983, Studies in "Standard Samples" of Silicate Rocks and Minerals 1969-1982: Canadian Geological Survey Paper 83-15, p. 114.

Flanagan, F.J., 1976, Descriptions and Analyses of Eight New USGS Rock Standards: U.S. Geological Survey Professional Paper 840, 192 p.

Gladney E.S., and Roelandts, I., 1988, 1987 Compilation of Elemental Concentration Data for USGS BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1, and STM-1: Geostandards Newsletter, 12:253-362.

Govindaraju, K., 1994, 1994 Compilation of Working Values and Descriptions for 383 Geostandards: Geostandards Newsletter, 18:1-158.

Return to top of page

Glossary

Symbol	Definition
Fe₂O₃T	Total iron expressed as Fe₂O₃
C_tot	Total carbon concentration
S_tot	Total sulfur concentration
Wt %	Percent of total element concentration
µg/g	Total element concentration expressed as micrograms of element per gram of solid sample
±	One standard deviation

Return to top of page

Notes

Unless otherwise indicated total element concentrations are reported for material on an as-received basis, i.e., no drying.

Return to top of page

Order and Pricing Information

Placing an Order

USGS reference materials (RMs) may be obtained directly from Dr. Stephen A. Wilson. The price for each RM 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 RMs 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 order form: Word format (48 KB) or PDF format (28 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
e-mail: (swilson@usgs.gov)

Payment Options

Domestic customers: Payment options include purchase order, check, money order, or credit card (Visa, Mastercard, American Express).

International customers: Payment on foreign orders can only be made using the following:

Banker's draft against an international bank
International money order
Credit card (Visa, Mastercard, American Express)

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

User Agreements

Beginning in 2006, users of USGS geochemical reference materials must complete a user agreement form prior to the order being processed. This agreement is required by the USGS Technology Transfer Office for complying with the United States Economy Act, 31 USC 1535A.

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

User agreement for domestic users: Word format, 48 KB and PDF format, 124 KB.
User agreement for foreign users: Word format, 52 KB and PDF format, 134 KB.

Get Adobe Reader Note: Some documents on this website are PDF files. Adobe Acrobat Reader is required to view them. Download free Adobe Acrobat Reader to view PDF files at the Adobe web site. Or go to Adobe's accessibility information for users with disabilities page.

Some documents on this site are Microsoft Office (.doc, .ppt, .xls) files. To view Office files, download Office Viewers or visit Microsoft Accessibility Technology for Everyone for assistive technologies.

Return to top of page

Back to Certificate List | Mineral Resources Program | Crustal Geophysics and Geochemistry Science Center

Mineral Resources	Eastern / Central / Western / Alaska / Minerals Information
	Crustal Geophysics and Geochemistry / Spatial Data