Where would I look if I was in a survival situation and wanted to find some rocks for fire starting? Where does flint occur naturally? What environments could you expect to find some in? I've created sparks by accident by throwing big rocks around here in the Canadian Rockies, like when making a fire ring, but if I were to go out looking for rocks that make spark I'd be lost as to what to look for and where. Where do you have good odds of finding stones that spark? How do you identify them besides the striking them to see if they'll make a spark?
Related: Is there a way to light a fire in the wild using rocks?