NIST Standard Reference Materials - SRM lists over 1300 individual reference materials produced by NIST, with carefully assigned values for chemical composition and physical properties. MSDS, prices in US$ and sale to registered users, dispatched from Gaithersburg, MD. - http://ts.nist.gov/ts/htdocs/230/232/232.htm
Brammer Standard Company, Inc. - Offers analytical reference materials for spectroscopy from around the world based in Houston, TX. - http://www.brammerstandard.com/
C.P.A. Chemical products for analysis - Offers standards and custom made, ready-to-use multi and mono-element solutions for AAS, ISP, MS and ILC, from Stara Zagora, Bulgaria. - http://www.cpachem.com/
Thorn Smith Laboratories - Quantitative and qualitative unknowns, student reference standards, answer sheets, from Beulah, MI. - http://www.thornsmithlabs.com/
Referenz Certified Reference Materials - Offer steel, iron and spectrochemical RM, PDF downloads include catalog from BAS CRM distributor for New Zealand and Australia. - http://referenz.atnz.net/
LGC Reference Materials - LGC produces and supplies high quality certified reference materials and biomaterials throughout Europe on behalf of ATCC, USP, EP, NIST and BCR. - http://www.lgc.co.uk/ref.asp
Resource Technology Corp. - RTC offers proficiency testing schedules, and manufacturers natural-matrix samples and certified reference materials in Laramie, WY. - http://www.rt-corp.com/
A.S.O. Design - Supplier of Canadian certified reference materials (standards) for calibration of analytical instruments, and ISO-9000. Consulting services are also provided in the fields of X-ray fluorescence (XRF), X-Ray diffraction (XRD) and Thermal Analysis (DTA-TGA) - http://asocanada.com/