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Hi Trevor, Interesting report. The photomicrographs are remarkably similar to ones I have of early-phase Central Wales galenas e.g Darren, Goginan, Talybont mines. See http://www.geologywales.co.uk/tetrahedrite.htm In Central Wales, such galenas carry abundant tetrahedrite (up to 20 wt% Ag), bournonite and ullmannite inclusions plus a range of other Co-Ni phases (including millerite)and traces of gold. Many Central Wales veins are multiphase. First active in Devonian times, there were phases of reactivation in the Carboniferous and Permian. Later mineralisation along existing and new fractures deposited galena that is pretty much inclusion-free and hence 5-10 times less argentiferous than the earlier stuff. Thus, some mines were getting 20-30oz Ag per ton whilst others just managed 3 to 7. I wonder if a similar pattern exists in the Combe Martin mining district? Cheers - John