How old are the oldest rocks in America, and where are they? How can I see them?
|An outcrop of Morton Gneiss in the Minnesota River valley|
Gneiss is a coarsely crystalline foliated
|Archean rocks in North America|
|This is classic geo-humor!|
But, you don't have to go to Morton to see the rock. The Morton Gneiss a widely-used building stone.
|Morton Gneiss on the exterior of Seattle's|
Exchange Building, 821 Second Avenue.
Learn more about the Morton Gneiss and see photos of cut rock used as building stone on my friend David Williams' website, 'Stories in Stone'. David is the author of Stories in Stone- Travels through Urban Geology which describes building stones used in the US and their origins all over the world. And here is another great website that describes and photographs the quarry operations.