 ... specimens of the rock. In the specimen analyzed about 5 per cent was found. In other specimens more is found, although in no case is it very abundant. It is clear and colourless, but is at once distinguished from the nepheline when examined between...  The American Journal of Science - Página 2721904Visualização completa - Sobre este livro
 | Royal Society of Canada - 1908 - 1112 páginas
...distinguished from the nepheline when examined between crossed niçois by its much higher polarization colours, which in thin sections frequently rise to a blue of the second order. It is free from interpositions, and in convergent light is seen to be uniaxial and negative. It also shows... | |
 | Frank Dawson Adams, Alfred Ernest Barlow - 1910 - 602 páginas
...distinguished from the nepheline when examined between crossed nicols by its much higher polarization colours, which in thin sections frequently rise to a blue of...dispersion of the bisectrices, giving a brownish and bluish tint on either side of the position of maximum extinction. When separated by Thoulet's solution,... | |
 | 1910 - 752 páginas
...distinguished from the nepheline when examined between crossed nicols by its much higher polarization colours, which in thin sections frequently rise to a blue of...dispersion of the bisectrices, giving a brownish and bluish tint on either side of the position of maximum extinction. When separated by Thoulet's solution,... | |
 | 1915 - 736 páginas
...colourless, and altogether free from inclusions or alteration products. In convergent light it is shown to be uniaxial and negative. It also shows a slight...position of maximum extinction. When separated by Thoulet heavy solution, it was found to have a specific gravity between 2.44 and 2.48. The amount of... | |
 | Alfred Ernest Barlow - 1915 - 560 páginas
...colourless, and altogether free from inclusions or alteration products. In convergent light it is shown to be uniaxial and negative. It also shows a slight...position of maximum extinction. When separated by Thoulet heavy solution, it was found to have a specific gravity between 2.44 and 2 . 48. The amount... | |
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