Clarification On Patina, Verdigris, Etc

The expert on this issue (certainly one of the experts) is listed on CCF as BadThad . He invented a product called Verdi-Care that many on this forum have used as a method of coin conservation.

Look him up in the section that lists CCF sellers, click on his name, and it should give you his email address. I'm confident there are many others on the forum who can help you as well. BadThad might just be a shortcut to the answers you seek. Best of luck. Jack

Patina is an attractive layer. If it looks like an ugly patch of verdigris or rust it's not a patina.

The word verdigris comes from the French vert de grece which means green of greece. The green of greece that forms on the copper components of buildings is referred to as patina, so why would it be different for coins? I'm just looking for verification or clarification.

The Green on anything Copper is due to the Copper combining with a form or Sulfur called Sulfuric or Sulfurous Acid. This creates a chemical reaction with the end results being Copper Sulfate which is a Greenish Crystal. However you don't see the crystals since they are so small on the surface of anything Copper. This is apparent on Copper pipes, Bronze statues, Copper Coins, etc. Then how can an Acid attack Copper? Where Sulfur rich coal is burned as a fuel, the Sulfur is released into the air and combines with Oxygen forming a mild Acid, Sulfurous Acid. If sufficient Oxygen is present, Sulfuric Acid too is formed and is in the air.

To describe a normal brown cent as having verdigris on it would be wrong... there is nothing green (and as you stated Verdigris comes from the French for green) just healthy patina.

Patina is signs of age on the surface of metal. It is used by pickers to mean rust but I think that rust and verdigris are subcomponents of patina.

The patina of a coin can be ugly (if it looks unnatural or unattractive) but generally how coin collectors use the word indicates an inert surface which has naturally aged.

I am not sure "the coin has a verdigris patina" is good English... but "the coin has a dark patina with some visable veridgris" would work.

The verdigris on that coin is ugly has a more sinister ring to it... it normally indicates that the surface is not inert...it is in the process of decomposition. (it is diseased and rotting)

Language is not an exact science... some words carry connotations not explained by their dictionary definition.... examples...

"conspiracy theory" means the belief that multiple people have acted in co-ordination to achieve a desired result. It carries the connotation of paranoia since it has been used in the media as a means of discrediting people who don't believe in the official spin put on events (It is fair to say that an individual conspiracy theory maybe be true or it may be false and that the official version of events might be a conspiracy theory but it won't be referred to as that)

Feminism - Officially this is the advocacy of women's rights on the ground of the equality of the sexes. One side of the fence will sincerely believe this is the case and state they believe in equality. The trouble being the word stems from the word female and the connotation suggests not equality but favouritism towards the female. Someone believing in human rights could be a humanist or gender egalitarian but when someone refers to themselves as feminist it summons the idea that they care only for women at the expense of men.

Whether these inferences are correct or not they do exist... and English draws from different regions... this means a choice between a word with French derivation or Germanic derivation in many cases. Though the two words might mean exactly the same the word with the French derivation will be regarded as sophisticated and the word with the Germanic derivation would be considered common. (etiquette/manner...purchase/buy...ensue/follow etc)

I go off at a tangent, but consider verdigris to have negative appeal and patina to be positive. Consider verdigris to be active degradation and patina to be inert. Consider green to generally be unhealthy verdigris and brown to be healthy patina (exceptions may exist)

It's all just semantics really. Any alteration of an original surface can be referred to as "patina". However, with coins, I consider corrosion to be something different from patina. I would classify any type of corrosion as just that - plain old corrosion which is damaging to coins. I do not consider verdigris (or rust) as part of a coins patina.