Picked up the October 2004 Mining Engineering issue with Greenland's mineral resources.
Bad news, there isn't much there that's been found so far to date. Disregarding cryolite, coal, graphite, iron, and marble as not worth shipping, zircon, molybdenum, uranium, and olivine as not usable with medieval or renaissance technology, we are left with copper and gold in the eighteen hundreds, and lead/zinc/silver around 1950, both before modern prospecting technology, and both in ice free areas eleven months a year.
They could ship ore to the lumber of Vinland or to the coal mines and smelt it there for a denser and more convenient shipping weight for transport to Eurpean markets. Also, once they started looking at Greenland's minerals, they would start looking down the coast till they got to warmer areas around New England and then started exploring North America.
Bad news, there isn't much there that's been found so far to date. Disregarding cryolite, coal, graphite, iron, and marble as not worth shipping, zircon, molybdenum, uranium, and olivine as not usable with medieval or renaissance technology, we are left with copper and gold in the eighteen hundreds, and lead/zinc/silver around 1950, both before modern prospecting technology, and both in ice free areas eleven months a year.
They could ship ore to the lumber of Vinland or to the coal mines and smelt it there for a denser and more convenient shipping weight for transport to Eurpean markets. Also, once they started looking at Greenland's minerals, they would start looking down the coast till they got to warmer areas around New England and then started exploring North America.