2015-CTP-13: Garnet Granulite

Title: 2015-CTP-13: Garnet Granulite
Description: The hand sample is mostly made of light-colored fine grains. There are some large garnet porphryoblasts. There is some very subtle lineation of dark colored minerals, possibly biotite, that form streaks. The thin section is made of large xenoblastic grains of mostly quartz, plagioclase feldspar that exhibits lamellar twinning, and some potassium feldspar evidenced by grid twinning. The texture of some these large grains looks to be granular and made of smaller equi-dimensional grains. There is random orientation and no foliation indicating a decussate texture. There were a large amount of garnet poikiloblasts at the top of the thin section but grinding unfortunately removed these grains. There appears to be a very small piece of garnet left behind but its optical properties seems to have been disrupted by being broken up. Also, there are a few grains that appear to exhibit undulose extinction. There could be possibly be a few kyanite grains.
Contributor: Bobby Sacchetta
Identifier: 2015-CTP-13
Mediator: Tamara Carley

Media: https://exhibits.lafayette.edu/geology/files/original/050ddc07dd9e49656db934b7b488e9c8.jpeg; https://exhibits.lafayette.edu/geology/files/original/56b87a5aac1e00b312d00881500eb81c.jpeg; https://exhibits.lafayette.edu/geology/files/original/244afebfed09f575a7852cad80597ba4.jpeg; https://exhibits.lafayette.edu/geology/files/original/265cbd2a02f13e7bc98f3a7c265341bd.jpeg; https://exhibits.lafayette.edu/geology/files/original/555c47176acf5565d5c422b386d4a808.jpeg; https://exhibits.lafayette.edu/geology/files/original/7f31b370aba68ef02d73af009f7a450d.jpeg; https://exhibits.lafayette.edu/geology/files/original/c826801b63481b49989439541050aaf0.jpeg; https://exhibits.lafayette.edu/geology/files/original/dd3aa93ce0053ddebc4afaa4c09ac8c3.jpeg; https://exhibits.lafayette.edu/geology/files/original/08ad5148685e0b5530b7affd9a939038.jpeg; https://exhibits.lafayette.edu/geology/files/original/ff99e8d925c5a1b73445181e4664c93a.jpeg; https://exhibits.lafayette.edu/geology/files/original/d1c57388b0b180dc921c75d84a810d3b.JPG; https://exhibits.lafayette.edu/geology/files/original/d45c224e1002af23fa7c030c11c14db3.JPG; https://exhibits.lafayette.edu/geology/files/original/8a3860ffdbf6f3404c1e9dc4598cb74e.JPG; https://exhibits.lafayette.edu/geology/files/original/aa97f1001ba362c75faddbffda89c2c3.JPG; https://exhibits.lafayette.edu/geology/files/original/e2feb2b1224a9bc828adccb24b833957.JPG; https://exhibits.lafayette.edu/geology/files/original/607b8787569f13ff932468c6991123d2.JPG

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