What does "incrustation" mean?

Incrustation: A crust or hard coating of anything upon or within a body, as a deposit of lime, sediment, etc., from water on the inner surface of a steam boiler.

Additional senses

  1. 2.(Arch.) A covering or inlaying of marble, mosaic, etc., attached to the masonry by cramp irons or cement.
  2. 3.(Fine Arts) Anything inlaid or imbedded.

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