Search results
Results from the WOW.Com Content Network
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 ]
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 ...
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 ...
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.
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 ...
Dark green, brown, gray, beige; colorless to pale green in thin section: Crystal habit: Rarely as distinct crystals. Columnar to fibrous and granular: Twinning: Simple and lamellar – common: Cleavage: Good on {110} intersecting at 54 and 126° Fracture: Splintery: Tenacity: Brittle: Mohs scale hardness: 5–6: Luster: Vitreous to silky ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The original scoring system was developed before the invention of pulse oximetry and used the patient's colouration as a surrogate marker of their oxygenation status. A modified Aldrete scoring system was described in 1995 [2] which replaces the assessment of skin colouration with the use of pulse oximetry to measure SpO 2.