lumachel

from The Collaborative International Dictionary of English v.0.48
Lumachel \Lu"ma*chel\, Lumachella \Lu`ma*chel"la\, n. [F.
   lumachelle, It. lumachella, fr. lamachella a little snail,
   dim. of lumaca a snail, fr. L. limax, -acis.] (Min.)
   A grayish brown limestone, containing fossil shells, which
   reflect a beautiful play of colors. It is also called {fire
   marble}, from its fiery reflections.
   [1913 Webster]
    

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