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The coral referred to in the Bible is the precious coral (Corallium rubrum), the formation of which is a calcareous secretion of certain polyps resulting in a tree-like formation. Presently coral is found in the Mediterranean , the northern coast of Africa furnishing the dark red, Sardinia the yellow or salmon-colored, and the coast of Italy ...
In the Gemara, the shamir (Hebrew: שָׁמִיר šāmīr) is a worm or a substance that had the power to cut through or disintegrate stone, iron and diamond. King Solomon is said to have used it in the building of the first Temple in Jerusalem in place of cutting tools. For the construction of the Temple in Jerusalem, which promoted peace ...
Diamonds are formed under the high-pressure, high-temperature conditions of the Earth's mantle. Kimberlites act as carriers for these diamonds, transporting them to the Earth's surface. The discovery of diamond-bearing kimberlites in the 1870s in Kimberley sparked a diamond rush , transforming the area into one of the world’s largest diamond ...
Diamonds are carbon crystals that form under high temperatures and extreme pressures such as deep within the Earth. At surface air pressure (one atmosphere), diamonds are not as stable as graphite, and so the decay of diamond is thermodynamically favorable (δH = −2 kJ/mol). [22]
Diamonds with higher color grades are rarer, in higher demand, and therefore more expensive, than lower color grades. Oddly enough, diamonds graded Z are also rare, and the bright yellow color is also highly valued. Diamonds graded D–F are considered "colorless", G–J are considered "near-colorless", K–M are "slightly colored".
It is possible to treat regular diamonds under a combination of high pressure and high temperature to produce diamonds that are harder than the diamonds used in hardness gauges. [30] Diamonds cut glass, but this does not positively identify a diamond because other materials, such as quartz, also lie above glass on the Mohs scale and can also ...
The high-pressure synthesis of diamond in 1953 in Sweden [21] [22] and in 1954 in the US, [23] made possible by the development of new apparatus and techniques, became a milestone in synthesis of artificial superhard materials. The synthesis clearly showed the potential of high-pressure applications for industrial purposes and stimulated ...
Synthetic diamonds of various colors grown by the high-pressure and high-temperature technique, the diamond size is ~2 mm. Infrared absorption spectrum of type IaB diamond. (1) region of nitrogen impurities absorption (here mostly due to the B-centers), (2) platelets peak, (3) self-absorption of diamond lattice, (4) hydrogen peaks at 3107 and ...