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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 ...
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith ) is subjected to temperatures greater than 150 to 200 °C (300 to 400 °F) and, often, elevated pressure of 100 megapascals (1,000 bar ) or more, causing profound physical or chemical changes.
A mixture of other minerals, often including pyrite. Lapis lazuli ( UK: / ˌlæpɪs ˈlæz ( j) ʊli, ˈlæʒʊ -, - ˌli /; US: / ˈlæz ( j) əli, ˈlæʒə -, - ˌli / ), or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color.
Opal is a hydrated amorphous form of silica (SiO 2 · n H 2 O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to its amorphous property, it is classified as a mineraloid, unlike crystalline forms of silica, which are considered minerals. It is deposited at a relatively low temperature and may occur ...
Graphite (/ ˈ ɡ r æ f aɪ t /) is a crystalline form of the element carbon.It consists of stacked layers of graphene.Graphite occurs naturally and is the most stable form of carbon under standard conditions.
Smaller deposits are found in South America (Brazil and Bolivia), Portugal, Romania, Burma and Russia. Hackmanite is found principally in Mont-Saint-Hilaire and Greenland. Euhedral, transparent crystals are found in northern Namibia and in the lavas of Vesuvius, Italy. Sodalitite is a type of extrusive igneous rock rich in sodalite. [16]
Stone carving is an activity where pieces of rough natural stone are shaped by the controlled removal of stone. Owing to the permanence of the material, stone work has survived which was created during our prehistory or past time. Work carried out by paleolithic societies to create stone tools is more often referred to as knapping.
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 ...