NorthStone is a particularly durable and dense granite found in the Ymira region. It is the main export of the Executioner-King's kingdom, who sells it to Gorshi, Karim, Voshurr, and Venigrad.
NorthStone has no particular properties which make it notable for offworlders, but is a critical resource on Saumai, which otherwise has little in the way of good stone sources.
"Maybe it's the cold what makes the rocks harder up that way. Northstone is harder than iron and heavier than your father's casket, and it makes the strongest walls."
I'm sure it takes some real tough folks to wrest it from the earth and drag it down our way, but the less I know, the better—Lucius hardly ever treats his workers in a way you'll want to hear about.
Look at us, reduced to fighting over rocks when once we flew among the stars.
Harder than Northstone.
Northstone is as blue as a deep lake in winter. The eyes say that the stone is black, but the heart says that there's a blue tinge just at the edge, where the stone intersects with the periphery of your vision.
Though the stone appears to have a fine grain and granule to its coloration, a sweeping hand will find only a comforting smoothness. It's a material which craves to be shaped into wonder, but which on this world is needed for the most basic infrastructure.