The amazing geology of a “granite” kitchen countertop

Reblogged from geologictimepics Rockin’ countertops–geologic time in our kitchens and bathrooms!

Compare this with my description of a single pebble here.  In these twice-metamorphosed slabs of rock, the fragment under high local stress (asterisked) is that little bit more soluble as a result, The beauty of rock structures is something that continues to amaze and delight me.

geologictimepics

I stopped by a “granite” supplier yesterday –the kind of place that sells “granite” and “marble” slabs for countertops.  Besides the fact that almost none of the slabs were actually granite or marble, they were spectacular rocks that showed wonderful wonderful detail. I nearly gushed at the idea of taking a geology field trip there.  It’s local, and you seldom find exposures like this anywhere else!

slabs of polished rock at a “granite” warehouse –most of it’s not actually granite, but it all reflects geologic time.

Generally speaking, “granite” in countertop language means “igneous” or “metamorphic” –crystalline rocks that form miles beneath Earth’s surface and so require great lengths of time to reach the surface where they can be quarried.  When I first started this blog, geologic time with respect to igneous and metamorphic rocks were some of the first things I wrote about –it’s such pervasive and important stuff.

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