10 ENGLISH BOOKS RELATING TO «PERTHITIC»
Discover the use of
perthitic in the following bibliographical selection. Books relating to
perthitic and brief extracts from same to provide context of its use in English literature.
The potassium-rich feldspar is orthoclase and perthitic with a fine tweed texture
arising from the monoclinic-triclinic transformation. Ab-rich plagioclase formed
during the coherent exsolution is commonly sufficient in amount to lead to ...
William Alexander Deer, Robert Andrew Howie, J. Zussman, 2001
2
Bedrock Geology of the Salem Quadrangle and Vicinity, ...
FELDSPARS NOMENCLATIVE The principal feldspar in rocks of the "alkalic"
series is a micro- perthitic intergrowth of microcline and sodic plagioclase. The
plagioclase of these intergrowths typically forms discontinuous, anastomosing, ...
3
Gems: Their Sources, Descriptions and Identification
Appearance Opaque to translucent, rarely transparent. Simple and polysynthetic
twinning are ubiquitous and perthitic intergrowth with albite, extremely common.
Reflections from incipient cleavages give polished surfaces a shimmering effect.
4
Selected Petrogenic Relationships of Plagioclase
Though these perthitic stringers may have been extended beyond the crystal
boundaries by external solutions, the environment of the porphyroblasts and the
absence of plagioclase veinlets, except those associated with the crystals, favor a
...
Richard Conrad Emmons, 1953
5
Antarctic Earth Science
Intrusives Russell Granite is a blue-grey, well foliated, often mafic rich biotite-
hornblende granite to granodiorite with large perthitic microcline phenocrysts and
minor anhedral perthitic orthoclase. Muscovite and remnant clinopyroxene are ...
R. L. Oliver, P. R. James, J. B. Jago, 1983
6
Introduction to Metamorphic Textures and Microstructures
... inclusions and the atomic structure of the host (Fig. 6.5). Unmixing of alkali
feldspar during cooling from high temperatures gives rise to exsolution
intergrowths of plagioclase (albite) and K- feldspar. This gives the characteristic
PERTHITIC ...
A. J. Barker, A. J. Barker (Ph. D.), 1998
7
Geological Survey Professional Paper
The most common minerals are (1) normally zoned plagioclase and (2)
porphyritic to poikilitic K-feldspar that lacks grid twinning and is locally perthitic.
The texture is hypidiomorphic-granular. In the silicic part, plagioclase is calcic
oligoclase; ...
Geological Survey (U.S.), 1988
8
U.S. Geological Survey Professional Paper
Subhedral perthitic microcline as much as 2 cm long; anhedral to subhedral
partly saussuritized and sericitized plagioclase (An2y) as much as 2 mm in
diameter; anhedral quartz as much as 2 mm in diameter in mosaic-textured
aggregates ...
9
Large Meteorite Impacts III
(A) Subhedral K-feldspar aggregate partially replacing anhedral perthitic
Archean feldspar grain (in extinction, center and left). Note that the plagioclase
blebs within the younger grains (arrows) are more rounded than in the Archean
grain but ...
Thomas Kenkmann, Friedrich Hörz, Alexander Deutsch, 2005
10
New Zealand Journal of Geology and Geophysics
Ortho- clase and microcline both frequently perthitic are the most abundant
feldspar and constitute the coarse feldspar laths. A few small quartz inclusions
are present in the coarse feldspar laths. Plagicclase is more abundant than in the
...