German ryakolith, from ryako- (from Greek rhyak-, rhyax stream, stream of lava) + -lith -lite; akin to Greek rhein to flow
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“Rhyacolite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rhyacolite. Accessed 11 Dec. 2023.
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