#kyanite — Public Fediverse posts
Live and recent posts from across the Fediverse tagged #kyanite, aggregated by home.social.
-
Repost: Kyanite isn't just a fetching blue mineral that documents the experience of sediments under extreme duress.
It's an ore: Virginia alone mined 83,000 tonnes in 2023. Kyanite in furnace insulation transforms to mullite when heated, expanding to reduce porosity and shrinkage.Virginia Kyanite (photo: J. Wyman) from:
https://energy.virginia.gov/geology/Kyanite.shtml -
This is one of the dykes found near Ayer's Cliff, just SE of Magog, Quebec. It's a set of three dykes, one of which has the deep-derived xenoliths. That one dyke (not photogenic) has weathered much faster, perhaps due to a higher carbonate content.
#kyanite #MinCup25 #Quebec #Xenolith #Grenville #Appalachians -
A photo of a Cretaceous dyke intruding into Appalachian-deformed sedimentary rocks deposited in the lower Paleozoic: Earth history from 110 to almost 500 million years ago.
But #kyanite records more of the story: it's part of xenoliths brought to the surface by these dykes that document Grenville crust (1.1 billion years old) at depth.
See: Trzcienski: Kyanite-garnet-bearing Cambrian rocks and Grenville granulites from the Ayer's Cliff, Quebec... Geology (1989)
#MinCup25 #Quebec #Appalachians