Update! Had some time to do some testing. Clearing up things:
1) The online map showed it as SAM ore.
2) Our save game, it is 100% uranium ore.
3) A just-started-new map it was quartz.
4) The save game, when only the host is connected, the above mentioned ore node does not crash the game.
5) The save game is seeing increasing number of crashes at different unrelated areas.