The Collaborative International Dictionary of English v.0.48:

Impearl \Im*pearl"\, v. t. [imp. & p. p. Impearled; p. pr. &
   vb. n. Impearling.] [Pref. im- in + pearl: cf. F.
   emperler.]
   1. To form into pearls, or into that which resembles pearls.
      [Poetic]
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            Dewdrops which the sun
            Impearls on every leaf and every flower. --Milton.
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   2. To decorate as with pearls or with anything resembling
      pearls. [Poetic]
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            With morning dews impearled.          --Mrs.
                                                  Browning.
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            The dews of the morning impearl every thorn. --R.
                                                  Digby.
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