Roros-Roraas and Miners

I have a question about the nature of this area of Sor Trondelag. In the 1801 census it is divided into parish and another area I believe to be a more rural area on the outskirts. The ancestors I am researching apparently migrated to this area and later moved on to work in the Kongsberg silver mines. What kind of mines were in Roros in the mid 1700's? Did the miners live on farms or housing associated with the mines? From searching the churchbooks it seems when they moved to Kongsberg they only attached Roros or Roraas to their name rather than a farm name. One unusual name used as a farm name is "Corporal". Anyone familiar with that place? Unrelated question - would Mogn an Moen be considered separate names, or Moens a corruption of Mogn?