Bank Of England Countermarks

As I mentioned in an earlier post, I like to collect Bank of England countermarks, which were applied to Spanish 8 reales (mostly from the Mexico mint), from 1797 to 1804.

There are two major countermark types (oval and hexagon). Both of these marks had genuine variations, and counterfeit variations. In addition, you can find the marks over both genuine 8 reales and contemporary counterfeit 8 reales.

Here is a contemporary counterfeit 8 reale (I believe it is GNL# 1794-O: Ga/R: Mo FM-005) with a likely counterfeit oval mark:





Here is one that I believe is a counterfeit hexagon mark over a genuine 1798 8 reale (or if the 8 reale is counterfeit, I can't match it to a GNL plate):





I am interested in any comments on these coins, or in hearing from anyone else who collects these countermarks. In particular, I would love to know if there is any definitive text for these issues. I have a 2003 article by Manville from the British Numismatic Journal that surveys older articles on these issues, but I don't know if there is any more recent resource.

Peter