8umn~ar 9. Chemical analyses, cell parameters, and optical properties are presented for seven Scottish orthopyroxenes: four from H~rris, two from Scourie, and one from Belhelvie, Aberdeenshire. The compositions range fl'om Ens~.6 to Enss. s-Six of the orthopyroxenes are from pyroxene granulites or related rocks and the other is from a plagiocla.~e-hypersthene hornfels: the latter mineral is notable in having 7.21% A1203, causing a considerable contraction in the a and b cell parameters. The

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... ina content of orthopyroxenes is briefly discussed. Analyses are also given for olivine and diopsidic augite from a South Harris ultrabasic gneiss and for two enderbitic pyroxene gnei~es from Seourie.