Another What Is It?

[Bryce]

Hoping someone can explain the geology of this rock. It's about a 250 pound rock found near Randolf SE of the metro. We were hauling sand out of a pit and at the bottom of the pit, the loader would encounter limestone when this beauty popped up. To my knowledge, limetone is sedimentary rock. This sure appears to have been molten at one time.

[Muskiefool]

I dont know but I like it

[Archerysniper]

I think that's what killed the dinosaurs.

[ThunderLund78]

I'm not a geologist, but it definitely look igneous. I took a Minnesota rock and minerals class in college and a very long time ago there was a lot of volcanic activity in the land that we now know as Minnesota. Most of the north shore rock was formed as a result of volcanic activity. Iron deposits are high from the iron-rich magma coming form deep within the earth settling near the surface. I suppose it's possible that some of that magma made its way down south. This is all according to my professor, he could've been full of it, too. he also said that the "mountains" we have up along the north shoe used to be as big as the rockies, but they've eroded down over millions of ears. It's apparently some of the oldest rock on the continent. Pretty cool!

[MOBY RICHARD*]

From what I can tell by the picture, it looks a lot like Basalt up by Taylors Falls, though the part that is lighter and smooth down in the lower middle area, appears to be flint like, if it is a little translucent...but I am no expert...

From a Websters Dictionary:

basalt n. black or dark gray rock, chiefly sodium or potasium alumino-silicates, with some iron, basic in character, supposed to constitute the bulk of the Earth beneath its solid crust, and found as intrusions at the surface in some places...

Well Randolf area must be some place...

Wikipedia gives a far more intricate and confusing explanation...

Check with others but if you are up in the Taylors Falls area stop in at the Northern part of the park...at the stoplight on Highway 8 take a right into the parking area, and look at the gray rock there and see if it looks similar enough...