Oxidation
This is when oxides or tarnish form on the surface of a coin. It is caused by exposure to dampness, industrial fumes, other elements, or even air.
Coin Collecting Terms beginning with the letter P
P ...
oxidation
The formation of oxides or tarnish on the surface of a coin from exposure to humidity, air pollutants, or other environmental elements.
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paper money
Paper notes with standardized characteristics issued as money.
oxidation: tarnish or corrosion on a coin caused by chemical reaction with its surroundings. Some tarnish is okay, any corrosion is bad.
P
patina: refers to the surface crust on an ancient coin or the color on a more modern coin.
OXIDATION
The formation of oxides or tarnish on the surface of a coin from exposure to air, dampness, industrial fumes, or other elements. Platinum, gold, and nickel do not oxidize except for a very thin film which is invisible to the naked eye.
Oxidation - The chemical reaction of metal with its surroundings. On copper coins, oxidation shows up as carbon spots and a mellowing of the origional color. On silver coints, oxidation shows up as tarnish or toning.
Oxidation
The chemical reaction on the surface of a coin, caused by exposure to air, dampness, industrial fumes, or other elements capable of reacting with oxygen.
Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds).
Spot of oxidation seen on a coin.
Carson City Mint
Located in Nevada, this mint produced gold and silver coins from 1870-1893.
The most common oxidation state of nickel is +2, though 0, +1 and +3 Ni complexes are observed.
Applications ...
Carbon spots are brown to black spots of oxidation that range from minor to severe -- some so large and far advanced that the coin is not graded because of environmental damage.
Often a form of tarnish or an oxidation type reaction with the coin's surface or something that has adhered to the coin's surface. Some times brownish yellow or red. See rust spots.BN - abbreviation for Brown.
These contaminants may be in the form of plain old-fashioned oxidation, environmental contaminants, lubricants, etc., that the planchets may have picked up before or while being struck.
Deeply toned, dark oxidation before Lincoln's portrait I B-279. Bronze. Plain edge (2). EF to AU, both later strikings (in our opinion). U.S. MINT OATH OF ALLEGIANCE I B-324. Bronze. Reeded edge. Proof-55. Battle Monument, Baltimore (a.k.a.
Judged from a numismatic standpoint the same form of oxidation takes on a more refined image, often enhancing a coin's value. After about 1980 the craze for attractively toned coins spurred some prehensile dealers to artificially tone their wares.
Without tarnish or oxidation, and with original cartwheel (i.e. frosty) or prooflike lustre. A copper coin is usually referred to as brilliant if it has full original red.
Si - Silicon an ingredient used in the manufacture of a few experimental base metal pattern coins having the ability to retard the oxidation that ordinarily accompanies similar, primarily aluminum or tin coins not having silicon added.
It might also be the result of oxidation produced by certain soils and moisture affecting the piece.
Prefix:
Letters or numbers in front of the serial number on a banknote.
Proof Like: ...
Safe and nonabrasive, removes oxidation and tarnish. Works on gold, silver, chrome, aluminum, copper, brass, stainless steel.
It kind of reminds me of toothpaste. Blue magic liquid metal polish works like magic on virtually every surface.
Copper pieces exposed to dampness will often exhibit oxidation and corrosion. Silver coins are also adversely affected by dampness.
This condition assumes that the coin has not been in circulation, only the patina and oxidation indicates that the coin is old. UNC is in its mint condition with all its mint sheen. No defect is acceptable.
Flyspecks - Minute oxidation spots on a coin, often caused by small droplets of spittle from talking over the coin.
Focal area - The area of a coin to which a viewer's eye is drawn. Liberty's cheek is the focal point of the Morgan Dollar.
Palladium has a resistance to oxidation, one reason palladium is growing in popularity for jewelry, especially in Asia.
GOLD: A precious yellow metallic element that is resistant to oxidation and is highly ductile and malleable. Gold has long been used as a store of wealth and a standard for currencies worldwide.
corrosion: some metals corrode due to oxidation, handling, or exposure to chemicals or moisture.
counterfeit: fake coins or currency that appear legitimate
currency: any kind of money that is legal tender ...
Natural coloring acquired by a coin as a result of oxidation produced by certain soils and moisture thereon.
Planchet
The disc of metal or other material on which the dies of the coin are impressed. Also known as a coin blank.
Flyspecks - Minute oxidation spots often seen on the surfaces of coins, particularly higher grade copper and nickel coins, caused by exposure to small drops of moisture.
If the silver coin you want to clean has only some small oxidation spots then you can clean then best with an acid fluid like warm vinegar or sour milk on a soft tissue or a raw potato cut in half and rub the coin with it.
surface due to loss of metal by corrosion planchet A piece of metal prepared for coinage with raised rims but as yet unstruck plugged Denotes that a holed coin has been filled porous Having a granular surface as the result of oxidation, ...
some metals corrode due to oxidation, handling, or exposure to chemicals or moisture.
Counterfeit
fake coins or currency that appear legitimate ...
Faience Ushabtis, Late Period, ca 1085-332 BC, approximately 90mm tall, blue glaze intact with some oxidation and erosion evident, features fairly clear, heiroglyphics on front untranslated and somewhat indistinct, fairly attractive, ...
Brilliant
Untoned. With no tarnish or oxidation, and with original cartwheel (frosty) or prooflike lustre. Copper coins are considered brilliant if they have full original red.
Patina: The green color found on copper coins usually caused by oxidation.
Pattern: A sample coin that could be used for circulation.
Planchet: A blank piece of metal used to receive a coin stamp.
A coin with a rough or granular/pitted surface from oxidation.
Prf
Proof. Type of coin production and / or Grade 60 -70 on the Sheldon grading scale.
Carbon spots
Detrimental oxidation specks appearing on the surfaces of a coin.
Patina - A green or brown surface film found on ancient copper and bronze coins caused by oxidation over a long period of time.
Pattern - An experimental or trial coin, generally of a newer design, denomination or metal.
Term for a numismatic item that is lack luster. This may be the result of cleaning, oxidation, or other environmental conditions.
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Also on PCGS.com ...
Powdery light green deposits, particularly in pits in the coin, are not patina but are an indicator of harmful oxidation, commonly referred to as bronze disease. Such coins must be treated to prevent further damage.
Porous - Having a granular surface as the result of oxidation, most frequently found with older copper coins.
The natural colouring acquired by a coin, token or medal over time. This colouring is often the result of oxidation or other chemical processes caused by contact of the coin's surface with the air.
Pattern ...
carbon spots - Spots seen primarily on gold and copper coins. Carbon spots are dark brown to black spots of oxidation. Carbon spots can decrease overall quality and value of a coin.
nickel coins (which are 75 percent copper) and silver coins (which are 10 percent copper). Carbon spots are brown to black spots of oxidation that range from minor to severe - some so large and far advanced that the coin is not graded because of ...
Patina applied to the surface of a coin, either by chemical or physical means, for the purpose of hiding hairlines and other flaws or to resemble the natural oxidation process that can increas a coin's desirability. See also TONING.
*GF9 SELEUKID COIN OF ANCIENT ISRAEL. Antiochus IX. 113-95 BC. AR Tetradrachm (14.25). Head of Antiochus right/Zeus standing left, hldg Nike. Houghton-814v, Hen-415. Toned VF, light oxidation. Ex Sugar collection. $325 [image] ...
High humidity or dampness will also result in oxidation or surface corrosion on coins. Silica or silica gel can be used in areas with high humidity when the coins are stored in a safe or lockbox.
The patina is the thin layer of tarnish (the effects of corrosion and oxidation) that develops on coins over many years.
which may or may not have been a contributing factor in their demise: these proofing techniques readily activated the metal surface. Although this was of limited importance on gold coins, the processes did accelerate the appearance of oxidation and ...
 See also: Silver, Gold, Coin, Copper, Half
  
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