I don't know. To buy shares of Glencar, traded in London as GEX, I went through an old "custodian account" that I still had left at one of the big banks. Their broker got it for me; the commission seemed high.
Presumably, big Canadian and US brokers can buy London stocks.
I might be interested in Cluff Gold too, mainly for Baohomun, if I can see a way to to rest easy owning something in Liberia or Sierra Leone. I still won't buy any Mano River, given a seemingly servile attitude towards Charles Taylor that I intuited. (Everything in business is character, both Junius and J. Pierpont Morgan claimed. I should have thought of that more while contemplating the enterprises of a family in S. Africa.)