Search results
Results from the WOW.Com Content Network
[5]: 132 Once used as a medicine [6] [7] and pharmaceutical preparation, [8]: 176 [9] verdigris occurs naturally, creating a patina on copper, bronze, and brass, and is the main component of a historic green pigment used for artistic purposes from antiquity until the late 20th century, including in easel painting, polychromatic sculptures, and ...
Brown or black can be used as a base color for copper patina. If the amount of chlorides decreases the color will be more bluish-green, if carbonate decreases, more yellow-green. [27] Black for copper. Solution of sodium polysulfide 2.5%, items must be submerged in the solution after color developing, wash, dry and wax or varnish colored object ...
The city of Mandeville was founded in 1834 by Bernard Xavier de Marigny de Mandeville (1785–1868). [3] The Marigny family was a prominent family of Louisiana, owning nearly a third of the city of New Orleans. The area had long been agricultural land when the town of Mandeville was laid out in 1834 by developer Bernard de Marigny.
In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. [12] Copper metallurgy was flourishing in South America, particularly in Peru around 1000 AD; it proceeded at a much slower rate on other ...
Shakudō (赤銅) is a Japanese billon of gold and copper (typically 4–10% gold, 96–90% copper), one of the irogane class of colored metals, which can be treated to develop a black, or sometimes indigo, patina, resembling lacquer.
Patina is also found on slip rings and commutators. This type of patina is formed by corrosion, what elements the air might hold, residue from the wear of the carbon brush, and moisture; thus, the patina needs special conditions to work as intended. Patinas can also be found in woks or other metal baking dishes.
Aside from the basic 25% silver to 75% copper mix, combinations as divergent as 5% silver to 95% copper are also marketed as "shibuichi". [1] A wide range of colours can be achieved using the whole range of alloy compositions, even above 50% silver, e.g. 90% copper and 10% silver for a dark grey and down to 70% copper and 30% silver for lighter greys.
The Tchefuncte site is located in the marsh a half-mile north of Lake Pontchartrain in eastern Louisiana. [3] The Tchefuncte site originally contained two oval-shaped shell middens, designated Midden A and Midden B. Midden A is about 52 meters long, 15 m wide, and 1.5 m thick.