ABSTRACT
Geological rocks and soils involve complex matrix compositions and their characterization is very difficult. Analysis of trace elements in soils and other silicate rocks seriously suffer due to the lack of availability of suitable silicate reference materials. Environmentally sensitive elements are of particular concern. In this paper, we discuss the procedures for characterization of the 27 trace elemental abundance in a new silicate reference sample of granitic composition (named as DG-H). A total number of about 2500 units of data for more than 50 trace elements were received from as many as 44 laboratories. The element wise data sets were subjected to rigorous statistical treatment to identify the outliers and subsequent rejection. Rest of the data, called “qualified data,” are therefore, used to estimate five estimators of central tendency, robust, as well as non-robust, viz., Mean, Median, Geometric Mean, Gastwirth Median, and Trimean. The arithmetic mean, called Preferred Mean (PM) of the above five estimates is assigned as Working Value or Recommended Value. As many as 23 elements are assigned recommended values, whereas rest four elements are found marginally less characterized. This reference sample would benefit the potential analytical community engaged in analysis of trace elements silicate in materials like rocks and soils.
ACKNOWLEDGMENTS
Authors are thankful to Dr. N. S. Virdi, Director (WIHG) for his encouragement and providing funding and other facilities for this work. This work could not have come to a reality without the contributions to the extensive database from a number of analysts from India and abroad. We gratefully acknowledge all of them for their cooperation.