Preparation of Reference Glasses for in-situ Analysis of Lithium and Boron.

In recent years there has been an increasing number of applications of micro-analytical techniques, such as Secondary-Ion Mass Spectrometry (SIMS) and Laser Ablation-ICP-MS, in the field of Earth Sciences. As a consequence, the need of well characterised calibration standards, which are a prerequisite for these techniques, has increased considerably. Such a request is particularly critical to SIMS due to the existence of matrix effects in the ion micro-probe analysis. In the present work we describe a technique to prepare a reference glassy sample starting from a powdered Standard Reference Material, represented by the basaltic rock JB-2 (Geological Survey of Japan), and report the results of EMPA and SIMS investigations for the characterisation of the resulting glass. We put a particular emphasis on Li and B owing to their importance as geochemical markers. We performed the in-situ analyses for the concentration of major-, minor-elements, as well as Li and B in the glassy material. The data testify that the glass could be employed as a reference material for Li and B elemental microanalysis. It is reasonable to foresee that the procedure proposed can be also applied to produce homogeneous glassy standards for in-situ Li and B isotope studies.