SRM 692 iron Ore (Labrador) is intended primarily for use in checking chemical methods of analysis and in calibration with instrumental methods of analysis. This data is public in the Certificate of Analysis for this material.

SRM 693 Iron Ore (Nimba) - Standard Reference Material 693 Iron Ore (Nimba) is material in the form of powder (<0.1 mm) for use in checking chemical methods of analysis and in calibration with instrumental methods of analysis. This data is public in the Certificate of Analysis for this material.

This Standard Reference Material (SRM) is in the form of chips sized between 0.50 and 1.18 mm sieve openings (35 and 16 mesh). It is intended for use primarily in chemical methods of analysis. Similar material for use in spectrometric methods of analysis is available as SRM 1297. This data is public in the Certificate of Analysis for this material.

Standard Reference Material 924a Lithium Carbonate - This Standard Reference Material (SRM) is intended for use as a chemical of known purity. It is intended primarily for use in the calibration and standardization of procedures and for the routine critical evaluation of the daily working standards used in these procedures. This data is public in the Certificate of Analysis for this material.

SRM 972a Vitamin D Metabolites in Frozen Human Serum - This Standard Reference Material (SRM) is intended for use as an accuracy control in the critical evaluation of methods for determining the amount-of-substance concentration of vitamin D metabolites in human serum. This SRM can also be used as a quality assurance tool for assigning values to in-house control materials for these constituents. This data is public in the Certificate of Analysis for this material.

This Standard Reference Material (SRM) is intended for use as a primary calibration standard for the quantitative determination of tellurium. A unit of SRM 3156 consists of five 10 mL sealed borosilicate glass ampoules of an acidified aqueous solution prepared gravimetrically to contain a known mass fraction of tellurium. The solution contains hydrochloric acid at a volume fraction of approximately 10 %, which is equivalent to an amount of substance concentration (molarity) of approximately 1.2 mol/L. This data is public in the Certificate of Analysis for this material.

This Standard Reference Material (SRM) is intended for use as a primary calibration standard for the quantitative determination of tungsten. A unit of SRM 3163 consists of 50 mL of an acidified aqueous solution prepared gravimetrically to contain a known mass fraction of tungsten in a high-density polyethylene bottle sealed in an aluminized bag.

SRM 3239 Isoflavones Calibration Solution - This Standard Reference Material (SRM) is intended primarily for use in calibration of instruments and techniques used for the determination of isoflavones. SRM 3239 consists of two solutions containing isoflavones at levels that reflect the mass fraction ratios found in soy products. This data is public in the Certificate of Analysis for this material.

This Standard Reference Material (SRM) is intended for use as an analytical standard of known potassium (K) and chloride (Cl-) content. This lot of potassium chloride (KCl) was prepared to ensure a material of high purity and homogeneity and has been assayed after drying at 500 °C. A unit of SRM 999c consists of a single glass bottle containing 30 g of the material. This data is public in the Certificate of Analysis for this material.

The Economic Census is the U.S. Government's official five-year measure of American business and the economy. It is conducted by the U.S. Census Bureau, and response is required by law. In October through December 2012, forms were sent out to nearly 4 million businesses, including large, medium and small companies representing all U.S. locations and industries. Respondents were asked to provide a range of operational and performance data for their companies.