The above is a copyrighted picture
reproduced here by permission. © 2008 by
[ Sources: Svens Adelsheraldik by Jan Raneke | Swedish Riddarhuset ]
Per fess.  Azure, a crown Argent.  Argent, an ouroboros Azure.
Baron Axel Fredrik Cronstedt (1722-1765) is best remembered for his discovery of nickel in 1751.
About 30% of the current World's supply of nickel comes from the region of the Sudbury Basin in Ontario, Canada. In 1951, Canada was supplying close to 90% of the World's nickel and commemorated the 200th anniversary of the discovery of nickel by issuing a 5-cent coin (Canadian nickel) designed by Stephan Trenka. The obverse sports an effigy of the British monarch (George VI, 1895-1952) and the reverse features a nickel refinery with a smokestack in the middle (with the words "Nickel 1751-1951" dexter). The coin is known in the trade as the Subdury Nickel. A monumental 30-foot replica of it, known as the Big Nickel, was first erected in 1954 in the City of Sudbury by a local businessman (Ted Szilva) who commissioned a local artist (Bruno Cavallo) for this. The coin is pure nickel, but the monument is made of stainless steel sheathing...
Cronstedt in History | NAHSTE | Wikipedia