(n.) An important ore of iron, the sesquioxide, so called because of the red color of the powder. It occurs in splendent rhombohedral crystals, and in massive and earthy forms; -- the last called red ocher. Called also specular iron, oligist iron, rhombohedral iron ore, and bloodstone. See Brown hematite, under Brown.
Example Sentences:
(1) The third aerosol, "gamma-oxide," has a MMAD of 0.73 micrometer and has crystalline subunits 0.2 micrometer in diameter; it is a magnetic form of hematite, gamma-Fe2O3.
(2) This case-control (case-referent) study concerns a worker population with high exposure to dust of iron oxides, particularly hematite, and with some impurities of pentavalent arsenic and other metals.
(3) The iron-oxides (superfine hematite) are eroded from the Peron Sandstone exposed in some coastal cliffs and constitute up to 2% of substrate sediments near these cliffs.
(4) Inside the molluscs, lower pH conditions cause reversal of the hematite charge and the cadmium is released and accumulated by the organism.
(5) These fungi were incubated with the following iron-containing minerals: augite, hornblende, biotite, magnetite, hematite, and the igneous rock granodiorite.
(6) The "feathers" hematite has a man median aerodynamic diameter (MMAD) of 0.17 micrometer and a large surface area because it is an agglomerate of units 0.005 micrometer in diameter.
(7) Slate is a metamorphic rock comprising silica, aluminum silicates, and small amounts of chlorite, hematite, magnetite, and various carbonates.
(8) In a retrospective cohort mortality study of 10,403 Minnesota iron-ore (hematite) miners no excesses of lung cancer mortality were found among either underground (Standardized mortality ratio [SMR] = 100) or above ground (SMR = 88) miners.
(9) The "birdshot" hematite has a MMAD of 0.31 micrometer, but has a smaller surface area because the subunits are 0.03 micrometer in diameter.
(10) Fibrous dusts (chrysotile, glass fibers, nemalite, palygorscite, and gypsum) and granular dusts (actinolite, biotite, hematite, pectolite, sanidine, and talcum) were injected intraperitoneally into rats.
(11) The mortality risk of nonmalignant respiratory disease among hematite workers in the Longyan and Taochong mines of China was investigated in a retrospective cohort study covering the period 1970-1982.
(12) No direct link between the cadmium loads in molluscs and its concentration in the water or substrate sediment is evident, but the cadmium load in molluscs is usually highest where turbulence is high and the substrate sediment contains fine hematite.
(13) Iron oxides, particularly hematite, have been suspected for carcinogenic properties based on epidemiological observations and experimental data.
(14) This study reveals that cadmium in the water adsorbs extremely efficiently onto the surface of the hematite, which is negatively charged at the prevailing seawater pH of 8.15, and that suspended hematite particles are ingested by the molluscs.
Sunstone
Definition:
(n.) Aventurine feldspar. See under Aventurine.
Example Sentences:
(1) To my surprise, the sunstone is "real" – or rather, as real as a firm theory can make it.
(2) A few months ago, an example of the sunstone was finally found, but in an Elizabethan ship: still hundreds of years away from the encyclopedia-like sources I would point to as a teen in order to "win" an argument.
(3) A great example is the "sunstone" Lothbrok uses for ship navigation in the show, a piece of seemingly magical rock that will light up with the sun's rays even on a cloudy day (the "sunstone" allows for the use of his sundial-compass even on long voyages, allowing him to eventually plunder England).
(4) Speculating on why a sunstone hasn't been found yet highlights how the simple passage of time can destroy our understanding of whole cultures.