Baron Axel Fredrik Cronstedt (/kroonstet/ 23 December 1722 – 19 August 1765) was a Swedish mineralogist and chemist who discovered the element nickel in 1751 as a mining expert with the Bureau of Mines.  
Cronstedt is considered a founder of modern mineralogy, for introducing the blowpipe as a tool for mineralogists, and for proposing that the mineral kingdom be organized on the basis of chemical analysis in his book Försök  til  mineralogie,  eller  mineral-rikets upställning (“An attempt at mineralogy or arrangement of the  Mineral Kingdom”, 1758).