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Decoupage or découpage ( / ˌdeɪkuːˈpɑːʒ /; [1] French: [dekupaʒ]) is the art of decorating an object by gluing colored paper cutouts onto it in combination with special paint effects, gold leaf, and other decorative elements. Commonly, an object like a small box or an item of furniture is covered by cutouts from magazines or from ...
Geode. A geode ( / ˈdʒiː.oʊd /; from Ancient Greek γεώδης (geṓdēs) 'earthlike') is a geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely spherical rocks, in which masses of mineral matter (which may include crystals) are secluded. The crystals are formed by the filling of vesicles in ...
Mineral evolution. Most minerals on Earth formed after photosynthesis by cyanobacteria (pictured) began adding oxygen to the atmosphere. Mineral evolution is a recent hypothesis that provides historical context to mineralogy. It postulates that mineralogy on planets and moons becomes increasingly complex as a result of changes in the physical ...
An amethyst geode that formed when large crystals grew in open spaces inside the rock. The largest amethyst geode found as of 2007 was the Empress of Uruguay, found in Artigas, Uruguay in 2007. It stands at a height of 3.27 meters, lies open along its length, and weighs 2.5 tons. Amethyst is also found and mined in South Korea. [19]
Vivianite is a soft mineral, with Mohs hardness only to 2, and specific gravity 2.7. It splits easily, with perfect cleavage perpendicular to the b- crystal axis, due to the sheet-like structure of the mineral. It is sectile, with a fibrous fracture, and thin laminae parallel to the cleavage plane are flexible.
The modern study of mineralogy was founded on the principles of crystallographyand microscopicstudy of rock sections with the invention of the microscopein the 17th century. [2] Europe and the Middle East. [edit] Theophrastus. The ancient Greek writers Aristotle(384–322 BC) and Theophrastus(370–285 BC) were the first in the Western ...
The rare-earth elements (REE), also called the rare-earth metals or rare earths or, in context, rare-earth oxides, and sometimes the lanthanides (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals.
Dispersion. None. References. [ 1] Moldavite ( Czech: vltavín) is a forest green, olive green or blue greenish vitreous silica projectile glass formed by a meteorite impact in southern Germany ( Nördlinger Ries Crater) [ 3] that occurred about 15 million years ago. [ 4] It is a type of tektite and a gemstone. [ 5]