A Summary of Progress in Petrography. in 1887-1896 |
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Page 1887
... brown . It is infusible before the blow- pipe , but at this high temperature it regains its original color . Its composition is : 9.44 7.14 SiO , NiO ZnO FeO CaO MgO As2O , H2O at 100 ° H2O at 600 ° 31.62 38.22 4.00 2.03 .70 .42 4.77 ...
... brown . It is infusible before the blow- pipe , but at this high temperature it regains its original color . Its composition is : 9.44 7.14 SiO , NiO ZnO FeO CaO MgO As2O , H2O at 100 ° H2O at 600 ° 31.62 38.22 4.00 2.03 .70 .42 4.77 ...
Page 1888
... brown color , a hardness of 4-4.5 , and Sp . Gr . of 4.485 . Occasionally groups of crystals with a ziron - like habit have been found . The mineral be- comes of a dull greenish hue after ignition , and is soluble in nitric acid ...
... brown color , a hardness of 4-4.5 , and Sp . Gr . of 4.485 . Occasionally groups of crystals with a ziron - like habit have been found . The mineral be- comes of a dull greenish hue after ignition , and is soluble in nitric acid ...
Page 1889
... brown tabular orthorhombic crystals , with a hardness of 4.5 , and Sp . Gr = 3.87 . Its composition is : 29. I 2.5 1.7 9.9 The As2O , Sb , O , Mn , O , Fe , O , MnO CaO MgO HO 20.2 1.5 35.8 .4 -Fouquéite . — In his excellent paper on ...
... brown tabular orthorhombic crystals , with a hardness of 4.5 , and Sp . Gr = 3.87 . Its composition is : 29. I 2.5 1.7 9.9 The As2O , Sb , O , Mn , O , Fe , O , MnO CaO MgO HO 20.2 1.5 35.8 .4 -Fouquéite . — In his excellent paper on ...
Page 1895
... brown . It is infusible before the blow- pipe , but at this high temperature it regains its original color . composition is : 9.44 SiO , NiO ZnO FeO CaO MgO As , O , H , O at 100 ° H , O at 600 ° 31.62 38.22 4.00 2.03 .70 .42 4.77 7.14 ...
... brown . It is infusible before the blow- pipe , but at this high temperature it regains its original color . composition is : 9.44 SiO , NiO ZnO FeO CaO MgO As , O , H , O at 100 ° H , O at 600 ° 31.62 38.22 4.00 2.03 .70 .42 4.77 7.14 ...
Page 1896
... brown color , a hardness of 4-4.5 , and Sp . Gr . of 4.485 . Occasionally groups of crystals with a ziron - like habit have been found . The mineral be- comes of a dull greenish hue after ignition , and is soluble in nitric acid ...
... brown color , a hardness of 4-4.5 , and Sp . Gr . of 4.485 . Occasionally groups of crystals with a ziron - like habit have been found . The mineral be- comes of a dull greenish hue after ignition , and is soluble in nitric acid ...
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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.