I have followed the discussion here with interest, and I hope you permit a foreigner who does not have English as first language to make some reflections. One of the things that are confusing with the English language is whether to write compound words like
mint mark like that or like
mintmark. Another good example is whether one should write
rail road,
rail-road or
railroad. All three spellings are used, but the last one dominates (at least according to Google). Especially confusing is it when different spellings give more or less different meanings, like
sometime and
some time. Anyway, sometime during my school time's English classes we were told that this reflects a development of the language, where to begin with two separate words are combined to form a term for a new concept (like
rail road). As time progresses, and the concept becomes more commonplace, the two words become one compound word,
railroad, sometimes with hyphenation,
rail-road, as an intermediate step.
So I cannot tell which is more correct, mint mark or mintmark. I probably use both, perhaps depending on which one I saw last (assuming that whoever wrote that is a native English speaker and knows better than me

).
It is much simpler in Swedish, where compound words are mandatorily written as a single word. So
mynt märke is wrong,
myntmärke is the only correct form (I am sure you can translate that into English, Swedish is not that different

). That of course can result in rather long words, that may look peculiar to speakers of other languages - for instance, pappersmasseindustriarbetarförbundsmedlemmarna* is a perfectly legal Swedish word (although unusually long, to be honest

).
* Translation: the members of the pulp and paper industry workers' union.