I don't recall having seen any coin shops in Copenhagen, but then again I haven't really been looking. I know there is one in Roskilde, which is only about half an hour away from Copenhagen by train. However, a search resulted in some addresses of these kind of shops in Copenhagen, look here and here. Coin shops are categorized together with stamp shops though, so some of the results may be exclusively stamp shops. You can tell from some of the names though what kind of shops they are knowing that the Danish word for 'coin' is 'mønt' and the word for 'stamps' is 'frimærker', but there are also quite a lot of the names that doesn't give any clue of this. Here are the addresses of some of the shops that appears to definitely have coins:

Coin Invest
Hjelmsgade 3
2100 København Ø

Plea Mønter
Gammel Kongevej 172
1850 Frederiksberg C

Amagerbro Mønthandel
Holmbladsgade 7
2300 København S

Brdr Høeg Poulsens Frimærke-Og Mønthandel
Smallegade 37
2000 Frederiksberg

Peter Flensborg Mønthandel & Forlag
Studiestræde 8
1455 København K

Frederiksberg Mønthandel
Gammel Kongevej 146
1850 Frederiksberg C

PRNcoins
Ålandsgade 5, st.
2300 København S

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