A Summary of Progress in Petrography. in 1887-1896 |
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Page 2
... symmetry be allowed to develop to the exclusion of the other two , there results an apparent hemimorphism , which in reality satisfies all the conditions of hemihedrism . The monoclinic plane of symmetry remains , so that the character ...
... symmetry be allowed to develop to the exclusion of the other two , there results an apparent hemimorphism , which in reality satisfies all the conditions of hemihedrism . The monoclinic plane of symmetry remains , so that the character ...
Page 3
... symmetry of crystals is intimately dependent upon the symmetry of arrangement of the atoms within the molecules . If this be true , all circularly polarizing bodies should possess an unsymmetri- cal molecule , which should reveal itself ...
... symmetry of crystals is intimately dependent upon the symmetry of arrangement of the atoms within the molecules . If this be true , all circularly polarizing bodies should possess an unsymmetri- cal molecule , which should reveal itself ...
Page 4
... symmetry , and isomorphous with arsenic , antimony , bismuth , and tellurium . In the pyroxene from Pinzgauer , Cathrein 22 has discovered the forms P , P , ZP 2 , all of which are new to the species . In amethyst from the Zillerthal he ...
... symmetry , and isomorphous with arsenic , antimony , bismuth , and tellurium . In the pyroxene from Pinzgauer , Cathrein 22 has discovered the forms P , P , ZP 2 , all of which are new to the species . In amethyst from the Zillerthal he ...
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... symmetry , a : b : c = .9939 : I : .6722 . The axial plane is the macropinacoid and c is the negative acute bisec- trix . 2Ena = 74 ° 15 ′ . Melinophane crystalizes in the tetartohedral division of the tetragonal system . Optically it ...
... symmetry , a : b : c = .9939 : I : .6722 . The axial plane is the macropinacoid and c is the negative acute bisec- trix . 2Ena = 74 ° 15 ′ . Melinophane crystalizes in the tetartohedral division of the tetragonal system . Optically it ...
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... symmetry when heated to 140 ° . Two varie- ties of the mineral are recognized . The first is a yellow variety to which the name katapleite is assigned , and the second a blue variety which is called soda - katapleite . The composition ...
... symmetry when heated to 140 ° . Two varie- ties of the mineral are recognized . The first is a yellow variety to which the name katapleite is assigned , and the second a blue variety which is called soda - katapleite . The composition ...
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Common terms and phrases
acute bisectrix Al,O Amer AMERICAN NATURALIST amphibole analysis andesites apatite augite axial ratio basalt biotite bisectrix brown Bull calcite Colby University color colorless composition containing cordierite corresponding described diabase diorites double refraction dykes Edited by Dr epidote eruptive Fe,O feldspar FeO CaO MgO FeO MnO Förh formula gabbro garnet Geol gneiss grains granite green ground-mass H₂O hardness hexagonal hornblende inclusions isomorphous Jour Kryst Lacroix lamellæ lithophysæ lustre magma magnetite MAKERS SYRACUSE manganese mica microlites mineral occurs MINERALOGY AND PETROGRAPHY.¹ molecule monoclinic Na,O Na₂O nepheline Neues Jahrb olivine optical angle optical axes original orthoclase orthorhombic Petrog PETROGRAPHY.¹ Petrographical phenocrysts plagioclase pleochroic porphyritic porphyritic crystals pressure prismatic produced pyroxene quartz regarded resembles rhombohedral rocks scapolite schists silica small crystals specific gravity spherulites structure substance symmetry thin section tion twinning plane variety W. S. Bayley Waterville yellow yielded Zeits
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Page 5 - The olivine is surrounded by a reactionary rim consisting of an inner zone of hypersthene and an outer one of actinolite.