As Napki indicated the Hungarian name for Kremnitz is Körmöcbánya, which is now Kremnica, Slovakia.
On the
medieval emissions (which is all that I am knowledgeable about) the K indicates the
mint and the other letter on the right
side of the coin indicates the moneyer. Several examples are as follows: (a) on a denar of Sigismund of Luxembourg (1387-1437), Huszar 578, the mark K—L indicates Kremintz, by Leonardo Bardi or Petrus
Lang, whereas K—R indicates Kremnitz, by Petrus Reichel, K—S indicates Kremnitz, by
Johannes Siebenlinder, and K—W indicates Kremnitz, by
Valentine Winche; (b) on a denar of the Interregnum (1445-1446), Huszar 614, K—I indicates Kremnitz, probably by Petrus Jung, whereas K—P indicates Kremnitz, by Konrad Polner; (c) on a denar of Matthias Corvinus (1458-1490), Huszar 704, K—A indicates Kremnitz, by Augistin Langsfelder, whereas K—S indicates Kremnitz, by Stephan Mikola; (d) on an
obol of Louis II (1516-1526), K—A indicates Kremnitz, by Alexius Thurzo, K—G indicates Kremnitz, by Georgius Thurzo, and K—H indicates Kremnitz, by Hans Thurzo. These marks are identified in Artur
Pohl’s book, Muenzzeichen und Meisterzeichen auf Ungarischen Muenzen
des Mittelalters 1300-1540.
During the reign of Rudolph (1576-1608), Huszar indicates that the denars were struck with the following marks: (a) no mark on Huszar 1054, 1055, 1056; (b) K—B on Huszar 1057, 1058, 1059, 1060; (c) H—S on Huszar 1061, 1062; (d) S—H on Huszar 1063; and (e) N—B on Huszar 1064, 1065 and 1066.
Huszar writes: “The
mintmark of the [Kremnitz]
mint in the Middle Ages was mostly a K, starting in the 16th century K—B, then from the middle of the 18th century B, in the end, since 1867 KB.”
It appears that Napki is correct with respect to the time-period of the two coins in question, although in the earlier period it was more complicated then that. Live and learn.