muschelkalk

from The Collaborative International Dictionary of English v.0.48
Muschelkalk \Musch"el*kalk`\, n. [G., from muschel shell + kalk
   limestone.] (Geol.)
   A kind of shell limestone, whose strata form the middle one
   of the three divisions of the Triassic formation in Germany.
   See Chart, under {Geology}.
   [1913 Webster]
    

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