Message:

<p>[QUOTE=&quot;lrbguy, post: 3110321, member: 88829&quot;]The Wikipedia paragraph is poorly written because it conflates too many phenomena into a single paragraph.&nbsp; They mention the formation of a green pigment on copper by the addition of acetic acid, and give the impression that the copper salt formed is a carbonate.&nbsp; ???&nbsp; Not so.&nbsp; It is a copper acetate.&nbsp; But they jumped the thought, and blew it.&nbsp;&nbsp; Altay is quite correct that Bronze Disease concerns the product produced when copper is acted upon by chloride ions.&nbsp; Verdigris is a common name for a whole class of substances chemically distinct from the two valence state copper chlorides.&nbsp; It is physically hard and only operates on the outer surface of a coin, forming a shell that will not progress deeper unless physically disturbed in a way that exposes the bare copper again.&nbsp; The chloride that is BD on the other hand, when exposed to humidity, produces an acid that will act on metal it contacts.&nbsp; The destruction is self sustaining, and will continue until all the copper is chemically used up, or it is arrested by external chemical alteration.</p><p><br /></p><p>[USER=33176]@Kentucky[/USER], I urge you to help set the record straight on the difference between bronze disease and verdigris by abandoning the all too common tendency among uninformed collectors to conflate the two.&nbsp; Coins are being mishandled.[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in