I played for a many hours this weekend, so maybe I miss some details 
I was ordered to investigate the mines near Skalitz. I entered them and have the cutscene with the miners (should all of the miners attack ? I killed the first one a after that all of them were running when they saw me. I think it was because of my perks, etc.). I have reached a path that seemed to me like and obvious exit, but I wanted to explore more. I took a very long ladder up. Met some of the miners and they fled. So I was chasing them in order to kill them. More and more were joining this new sport. So in the end the coridors were overcrowded and I finally catch one of them. But he didnt want to die , turn a round and run the other side. I saw, that the others are far away so I decided to finish that unfortunate bastard. I completly lost my way. Couldn´t find the ladder. Luckily I chaste other miners and they led me to some exit. I was on top of a hill, went downhill, met bandits, kill them and entered the mines again. Cutscene with some guy making fake coins. Arrested him, Cutscene with Florian (?) in Sasau and the quest to investigate the fake coins completed. In this quest I only spoke with Florian in Rattay and he told me I should ask about the quicksilver in Sasau. Also I have met the old “knight” from Passau investigating as well.
Question is: How long is this quest? (like in a real time 
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