Boron distributions in single crystals investigated with nuclear reaction micro analysis

Crystals synthesised in the laboratory in B-rich fluxes were analysed with a nuclear microprobe and nuclear reaction techniques for boron distribution and concentration determination. The synthesis technique and the principles of the elemental analysis are discussed and some analytical examples are shown. The geological problem, a B-Si substitution, is described with some conclusions. The zonal B-pattern observed in Mn3+-substituted diopside clearly demonstrate that the present analyses represent structurally bound B and the observed variation in Na- and B-concentration ratios provide evidence for a decoupling of the suggested substitution mechanisms in clinopyroxene. (C) 1999 Elsevier Science B.V. All rights reserved.