Everyone intersted in minerals and mineral collecting will want to have useful little book close at hand, either for field use or home study. It has been especially designed to give the beginner a knowledge of mineralogy that will greatly increase his enjoy ment of it. The book begins with a definition of the mineral as a naturally occuring chemical element or compound formed as a product of in…
This study deals with the massive Elvaberget sulphide deposit, in the southern part of the central skellefte district. The ores as well as the surrounding rocks and alteration zone were studies.
The major role played by magma mixing processes in the origin of intermediate lavas (andesites of the calco-alkalic series and trachy-andesites of the alkalic series) is demonstrated by four different features : 1. Frequent, 2. Position of the lava mixtures, 3. Role played by the transfer of phenocrysts, 4. Geochemical control
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