# Practical Aspects of Mineral Thermobarometry

## Reciprocal solutions

In multi-site solid solutions, it may be necessary to consider
non-ideal interactions between cations in different sites as well as,
or rather than, interactions in the same site. This is entirely understandable
in terms of mineral structure: for any cation site of interest, its nearest
cation neighbours are quite likely to sit in a crystallographically different
site. Such relations are
called *reciprocal*, and they are described in Spear, chapter 7,
pp. 205-213. An activity model for disordered sodic pyroxenes
involving reciprocal solution parameters is given in Holland (1990)
Contrib Min Pet 105, 446-453.

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This page last modified 12 October 2004