SY-2, SY-3 and MRG-1 Report on the collaborative analysis of three canadian rock samples for use as certified reference materials - supplement 1

Abstract

Additional data received since the original report, MRP/MSL 75-132(TR), was prepared, are presented. New recommended values are assigned to several constituents.

Calibration standards

“…Valcha, 1972) describe wellestablished values as 'guaranteed', in contrast to merely 'recommended'. Still others (Beyers, 1974) have issued 'certificates of analysis' that listed only 'average' or 'magnitude' values. in this report as in earlier work (Abbey, 1972(Abbey, , 1973(Abbey, , 1975a, the term 'usable values' signifies values that can be used for most purposes. However, varying degrees of uncertainty persist (see below), and therefore changes in 'usable values' may be expected as more analytical data become available.…”

“…(5) Where 10 or more results were available, they were plotted in a 'numerical histogram' (Abbey, 1970;Abbey et al, 1975a). Because of the manner in which the histograms were subsequently used, the choice of class intervals was not based on statistical rules, but was made in a manner to accentuate model peaks, and preferably to provide seven or more intervals.…”

“…On the basis of this writer's studies of the data emanating from collaborative programs originating in the USA (Flanagan, 1969), the United Kingdom (Poole, 1972), France (Roubault et al, 1970;de La Roche and Govindaraju, 1973a, b), the Soviet Union (Kukharenko et al, 1968), Japan (Ando et al, 1971(Ando et al, ,1974, South Africa (Russell et al, 1972) and Canada (Abbey et al, 1975a) the bulk of the evidence points to inter-laboratory factors as the major source of discordant data. That is not to deny the importance of sample homogeneity, sub-sample weight, fineness of grindmg, the need to perform controlled replicate analyses nor the usefulness of statistical data on methods.…”

“…Observations made in the course of studying compilations of analytical data on many different 'standard samples' (Abbey, 1970(Abbey, , 1972(Abbey, , 1973(Abbey, ,1975a have led to certain conclusions which have met with varying degrees of acceptance by others working in the same field. These conclusions follows:…”

Comparative Determination of Uranium In Silicates by Delayed Neutron Activation Analysis

“…Also i n c l u d e d i n T a b l e 1 are t h e NBS c e r t i f i e d v a l u e s a s w e l l as CCRMP c e r t i f i e d v a l u e s and " p r e f e r r e d " v a l u e s g i v e n by(15)(16)(17)(18)(19)(20)(21)(22). The mean v a l u e , w i t h one s t a n d a r d d e v i a t i o n among 3-9 d e t e r m i n a t i o n s a t e a c h l a b o r a t o r y , is r e p o r t e d .The f i n a l column i n d i c a t e s t h e r a t i o o f t h e LANLt o TAMU a v e r a g e uranium c o n c e n t r a t i o n s f o r each r e f e r e n c e material.…”