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#kyanite — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #kyanite, aggregated by home.social.

  1. Bill Minarik @silicatefondue ·

    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:
    energy.virginia.gov/geology/Ky

    #mincup25 #kyanite #mullite #virginia #appalachians
  2. Bill Minarik @silicatefondue ·

    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
  3. Bill Minarik @silicatefondue ·

    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 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)

    #kyanite #mincup25 #quebec #appalachians