Chemically analyzed Precambrian igneous and metamorphic hornblendes in general do not confrom to the same patterns in a region of high-grade metamorphism where hornblende compositons are dependent primarily on the mineral assemblage.
Looking mainly at the amphiboles, this volume has added sections on deerite, howieite and multiple-chain silicates (biopyriboles). This edition includes results of recent research into amphiboles. Each chapter is headed by a brief tabulation of mineral data and a sketch showing optical orientation. Diagrams of the crystal structures are presented and followed by discussion of the structural features, making use of data from spectroscopic and diffraction experiments. The chemical sections include over 550 analyses from which structural formulae have been calculated, illustrating the range of chemical and paragenetic variation exhibited by each mineral. There are results of P-T experiments, thermochemical and computer modelling techniques. The principal modes of occurrence are described in the paragenesis sections emphasizing correlations with chemistry.
Chemically analyzed Precambrian igneous and metamorphic hornblendes in general do not confrom to the same patterns in a region of high-grade metamorphism where hornblende compositons are dependent primarily on the mineral assemblage.
February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index
1919/28 cumulation includes material previously issued in the 1919/20-1935/36 issues and also material not published separately for 1927/28. 1929/39 cumulation includes material previously issued in the 1929/30-1935/36 issues and also material for 1937-39 not published separately.