First of all, for the lack of a better summary of what these dwarves were all about, here are a couple of quotes from Wikipedia. I checked the original sources and they look legit, so this ought to be accurate:
Dvergar or Norse dwarves (Old Norse dvergar, sing. dvergr) are entities in Norse mythology associated with rocks, the earth, deathliness, luck, technology, craft, metal work, wisdom, and greed. They are sometimes identified with Svartálfar ('black elves'), and Dökkálfar ('dark elves'), due to their apparently interchangeable use in early texts such as the Eddas. While the word "Dvergar" is related etymologically to "dwarves", the early Norse concept of Dvergar is unlike the concept of "dwarves" in other cultures. For instance, Norse dwarves may originally have been envisaged as being of human size. ... The Dvergar are often called 'black', especially as the 'black elves' (svartálfar). In Old Norse, this byname 'black' (svartr) refers to hair color or eye color.
The illustration above is of Reginn the Dvergr, again courtesy of Wikipedia. Now here's an abstract from a recent open access paper on maritime contacts between the East Mediterranean and Scandinavia during the Bronze Age. Note the references to rocks, technology, craft, metal work and trade (and thus greed, I suppose).
The Bronze Age of Scandinavia (1750-500 BC) is characterized by the sudden appearance of bronze objects in Scandinavia, the sudden mass appearance of amber in Mycenaean graves, and the beginning of bedrock carvings of huge ships. We take this to indicate that people from the east Mediterranean arrived to Sweden on big ships over the Atlantic, carrying bronze objects from the south, which they traded for amber occurring in SE Sweden in the Ravlunda-Vitemölla–Kivik area. Those visitors left strong cultural imprints as recorded by pictures and objects found in SE Sweden. This seems to indicate that the visits had grown to the establishment of a trading centre. The Bronze Age of Österlen (the SE part of Sweden) is also characterized by a strong Sun cult recorded by stone monuments built to record the annual motions of the Sun, and rock carvings that exhibit strict alignments to the annual motions of the Sun. Ales Stones, dated at about 800 BC, is a remarkable monument in the form of a 67 m long stone-ship. It records the four main solar turning points of the year, the 12 months of the year, each month covering 30 days, except for month 7 which had 35 days (making a full year of 365 days), and the time of the day at 16 points representing 1.5 hour. Ales Stones are built after the same basic geometry as Stonehenge in England.Interesting stuff. The only thing I'd add is that these contacts between the Mediterranean and Scandinavia most likely stretched back to the Neolithic, when Megalithic cultures dominated Southern and Western Europe. Indeed, the remains from a TRB (Funnelbeaker) Culture burial in western Sweden were recently genotype for autosmal DNA and they came out surprisingly Mediterranean (see here). Nils-Axel Mörner, Bob G. Lind, The Bronze Age in SE Sweden Evidence of Long-Distance Travel and Advanced Sun Cult, Journal of Geography and Geology, Vol 5, No 1 (2013), DOI: 10.5539/jgg.v5n1p78