Search results
Results from the WOW.Com Content Network
Closely spaced polysynthetic twinning is often observed as striations or fine parallel lines on the crystal face. Cyclic twins are caused by repeated twinning around a rotation axis. This type of twinning occurs around three, four, five, six, or eight-fold axes, the corresponding patterns are called threelings, fourlings, fivelings , sixlings ...
The mineral usually has polysynthetic twins, which are only visible in thin sections when the specimen is inspected under polarized analyzed light. [4] Analcime mainly consists of oxygen (50.87%), silicon (25.51%), aluminum (12.26%), sodium (10.44%) but otherwise has a negligible amount of hydrogen (0.92%) as well. [ 5 ]
Ulexite displays polysynthetic twinning parallel to the elongation, along {010} and {100} (Murdoch, 1940). [11] In thin sections cut parallel to the fibers, ulexite grains display both length-fast and length-slow orientations in equal quantities because the intermediate axis (y) of the indicatrix is roughly parallel to the elongation of the ...
[1]: sections 1-2 The size of the margin is an important issue in areas that are functionally important (i.e., large vessels like the aorta or vital organs) or in areas for which the extent of surgery is minimized due to aesthetic concerns (i.e., melanoma of the face or squamous cell carcinoma of the penis). [2]
Plagioclase displaying cleavage. (unknown scale) In volcanic rocks, fine-grained plagioclase can display a "microlitic" texture of many small crystals. Plagioclase (/ ˈ p l æ dʒ (i) ə ˌ k l eɪ s, ˈ p l eɪ dʒ-,-ˌ k l eɪ z / PLAJ-(ee)-ə-klayss, PLAYJ-, -klayz) [4] is a series of tectosilicate (framework silicate) minerals within the feldspar group.
Craniopagus parasiticus is an extremely rare type of parasitic twinning occurring in about 4 to 6 of 10,000,000 births. [1] In craniopagus parasiticus, a parasitic twin head with an undeveloped body is attached to the head of a developed twin. Fewer than a dozen cases of this type of conjoined twin have been documented in literature.
Timothee´Chalamet, left, sang Bob Dylan's songs himself in the new biopic "A Complete Unknown."
Green to dark green; colorless to pale green in thin section: Crystal habit: Rarely in rough crystals; anhedral, granular to massive: Twinning: Single and polysynthetic twinning common on {100} Cleavage: Good on {110}, {110} ^ {1 1 0} ≈87°; parting on {100} Fracture: Uneven to conchoidal: Tenacity: Brittle: Mohs scale hardness: 5–6: Luster ...