silvering

/S IH1 L V ER0 IH0 NG/
verb
  1. 1

    To acquire a silvery colour.

  2. 2

    To cover with silver, or with a silvery metal.

    โ€œto silver a pin;โ€‚ to silver a glass mirror plate with an amalgam of tin and mercuryโ€

  3. 3

    To polish like silver; to impart a brightness to, like that of silver.

  4. 4

    To make hoary, or white, like silver.

noun
  1. 1

    The process of coating a surface with a thin layer of silver (or a similar metal), especially so as to form a mirror.

  2. 2

    The silver used in this kind of coating.

Source: https://en.wiktionary.org/wiki/silver, https://en.wiktionary.org/wiki/silvering