A Summary of Progress in Petrography. in 1887-1896 |
From inside the book
Results 1-2 of 2
Page
... melanophlogite has been made the subject of recent study by Friedel 12 and by Streng.13 The former writer has examined the apparent cubes of the mineral in polarized light , and has found them to consist of six tetragonal pyra- mids ...
... melanophlogite has been made the subject of recent study by Friedel 12 and by Streng.13 The former writer has examined the apparent cubes of the mineral in polarized light , and has found them to consist of six tetragonal pyra- mids ...
Page
William Shirley Bayley. = tetragonal melanophlogite . Analysis of these gave SiO , = 93.2 per cent . , SO , 5.7 per cent . This substance loses twelve per cent . of its weigh ton heating , while the tetragonal mineral loses six per cent ...
William Shirley Bayley. = tetragonal melanophlogite . Analysis of these gave SiO , = 93.2 per cent . , SO , 5.7 per cent . This substance loses twelve per cent . of its weigh ton heating , while the tetragonal mineral loses six per cent ...
Other editions - View all
Common terms and phrases
acid Al,O alteration Amer AMERICAN NATURALIST analysis andalusite angle aragonite augite axial ratio basalts beryl biotite brucite Bull calcite calcium chlorite cleavage Colby University color colorless composition constituents containing cordierite corresponding crystalline crystals density described diabase double refraction dyke eruptive rocks Fe,O Fe₂O feldspar FeO MgO CaO FeO MnO forms formula Franc gabbro-diorites gabbros garnet Genth gneisses granite granulites ground-mass H₂O habit hexagonal hornblende humite hypersthene imbedded inclusions Jour Kryst leucite masses melanophlogite metacinnabarite mica mineral MINERALOGY AND PETROGRAPHY.¹ Mitth molecules muscovite Neues Jahrb nosean occur olivine optical original orthoclase ottrelite parallel Penfield Petrog PETROGRAPHY.¹ Petrographical phenacite plagioclase plane plates polymorphism prismatic produced pseudomorphs pyroxene quartz regarded rock individual Rosenbusch schistose schists serpentine silica sodium soluble specific gravity specimens spinel structure substance sulphur symmetry tabular temperature tonalite tourmaline twinned varieties W. S. Bayley Waterville yielded Zeits zircon zone
Popular passages
Page 19 - The plane of the optical axes is perpendicular to the plane of symmetry, and makes with c an angle of °7 in acute /9. A = b. 2H na = 104° 27'.
Page 14 - The larger part of the dust is thought to be a sediment from the air, and to have been obtained by it from a region of crystalline schists. The chondri, on the other hand, are thought to be of cosmic origin, since they are similar to the chondri obtained in deep-sea soundings. If the amount of the dust collected from the snow in Greenland represents the fall of one year, the total amount falling upon the entire surface of the earth in this time is 125 million kilograms, equivalent to a cube of thirty-one...
Page 14 - Wiilfing 21 for investigation, by whom it has been found to consist in greater part of feldspar, quartz, mica, and hornblende. There are present in it also garnet, zircon, magnetite, augite, and sillimanite, and with them is mixed a nitrogenous organic substance. The most interesting constituents of the dust...