Beat a mine's guards, land and raise your flag: it pays every sea day. Up to 7 mines.
1At a mine the prompt says what it needs: «guards stand before the mine: beat them first». A mine held by raiders wants a party at least as big as their garrison (4, 8 or 14 men).
2Guards beaten: press «Land» (key L) by the mine.
3«Raising the flag»: 20 seconds. A fresh flag is safe for 10 minutes.
4Your flag flies: the yield goes to your island every sea day (48 minutes) — a silver mine 250 a day, timber 14, iron 7, tar 10, powder 5, pearls 1, rum 8; ×0.75 in safe waters, ×1.5 in lawless ones. Without an island it piles up at the mine, up to a week.
5Mines are on the chart's «All» layer: «Your mine», «· raiders», «· nobody's». You hold at most 7; raiders may come for a mine once in a while.