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Mining ships are described in more detail here. Essentially, Mining ships will collect harvestable resources that the stations needs if they can carry it and typically, a Mining ship cannot carry both Bulk and Liquid resources.
Advantages of smaller ships are speed and lower cost, but coming with the disadvantages of weaker defences (especially medium ships) and cargo type restriction (although since multiple ships are typically needed by complete stations, this is of debatable significance). Advantages of larger ships typically include sturdier defences, greater storage capacity and the option of ships that can carry any cargo. Downsides of large, slow ships for stations include longer delivery runs and the potential for all their cargo space not being needed for a given run.
Ship assignments: Manager
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