Daveydempsey you are correct it is copper over steel. I think you a correct for the assessment of the cause.
Larry. it would be best to start your own thread. The ones who look at these coins are the same folks that will look at your coins.
Hi Larry , www.predecimal.com I absorb decades of knowledge from Peter , Chris , and Colin on the website and forum . They have an extensive encyclopedia of British coins . Have a look .