Kies

noun
  1. A term used in mineralogy to refer to certain sulfide minerals, especially those containing iron and copper. noun
    The geologist discovered a rich deposit of kies in the mine.
    Kies minerals are often associated with the presence of valuable metals.
  2. A variant spelling of 'keys', referring to devices used to open locks or to operate mechanisms. noun
    She couldn't find her kies and was locked out of her house.
    The janitor carries a large ring of kies for all the doors in the building.