spongiolite

from The Collaborative International Dictionary of English v.0.48
Spongiolite \Spon"gi*o*lite\ (-[-o]*l[imac]t), n. [Gr. spoggia`
   sponge + -lite.] (Paleon.)
   One of the microscopic siliceous spicules which occur
   abundantly in the texture of sponges, and are sometimes found
   fossil, as in flints.
   [1913 Webster]
    

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