The Collaborative International Dictionary of English v.0.48:

Gem \Gem\ v. t. [imp. & p. p. Gemmed; p. pr. & vb. n.
   Gemming]
   1. To put forth in the form of buds. "Gemmed their blossoms."
      [R.] --Milton.
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   2. To adorn with gems or precious stones.
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   3. To embellish or adorn, as with gems; as, a foliage gemmed
      with dewdrops.
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            England is . . . gemmed with castles and palaces.
                                                  --W. Irving.
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