Thursday, April 8, 2010

mica trail



A brownstone slab functioning as a banister on a stoop near my house has streams of Muscovite running through. I don't recall I've seen brownstone with this kind of inflection before, but perhaps what I saw when I thought I saw brownstone was actually brownstucco. The traces of mica remind me that the sandstones that ornament Brooklyn, according to Williams' Stories in Stone, are the product of flooding that loaded an ancient valley with sand, silt and pebbles that then hardened into an aggregrate, tinted brown with iron, giving impermanence another go round, maybe a little like scrapple. I assume that the weathering seen on the bottom of the slab tells us that this chunk was rotated 90 degrees from its bedding position and gravity is now helping to separate the layers.

2 comments:

David B. Williams said...

Amarilla,
Nice photo of the flickering mica. Always fun to see those thin sheets twinkle in the light.
David

amarilla said...

I've been eyeing mica so long I think it's more or less a member of the family. Speaking of family members, I'd love to aquaint you with my father, geologist Bill Melson. http://mineralsciences.si.edu/staff/pages/melson.htm

He'll really love your book.