SRM 614/615 - Trace Elements in Glass

SRM 614/615 - Trace Elements in Glass

These Standard  Reference Materials (SRMs) were produced and certified to facilitate the development of chemical methods of analysis for trace elements and is one of a series of four pairs of SRMs.  For both SRMs, 614 and 615, the nominal trace element concentration is 1 mg/kg for each of the sixty-one elements that have been added to the glass support  matrix. The two SRM..s differ only in the thickness of the glass wafer. Units of SRMs 614 and 615 are issued as sets of six wafers.

These materials were prepared in rod form and have been sliced into wafers.  The roäs were hand-pulled, and therefore are not uniform over their length.  Each wafer is oval to circular in cross-section, with a nominal diameter of 12-14 mm. The certified values are for an entire wafer (no fragment thereof).  The debris from wafering has been only partially removed and each wafer should be surface cleaned before use. The first step in preparing the wafer for analysis is to wipe it clean with alcohol, and then to give it a mild surface cleaning (not etch) in dilute (1:10)
nitric acid. The wafers were cut with a copper-bonded diamond wheel and the nitric acid step is included to remove any possible copper contamination.

Considerable care and effort have gone into the manufacturing of these SRMs to ensure homogeneity.  The target Ievel of precision and accuracy for certification of thesematerialswas 10 percent or better.    To date no element has been proven tobe heterogeneaus outside this Iimit for the SRM wafer used in its entirety. However, spatial inhomogeneity does exist within each wafer.  For certification, two or  more methods or laboratories must agree to at least the target Ievel.
 

keywords: geological materials , trace elements , heavy metals , direct solid sample analysis

Units of SRMs 614 and 615 are issued as sets of six wafers.

3 mm wafer: SRM 614

1 mm wafer: SRM 615