quartz
noun /kwɔːts/
  /kwɔːrts/
[uncountable]- a hard mineral, often in crystal form, that is used to make very accurate clocks and watches- The watch runs with a normal quartz movement.
 Oxford Collocations DictionaryQuartz is used before these nouns:- crystal
- watch
 Word Originmid 18th cent.: from German Quarz, from Polish dialect kwardy, corresponding to Czech tvrdý ‘hard’.