{{Short description|English gold coin of the reign of James I}} {{other uses}} {{Use dmy dates|date=April 2022}} A '''Jacobus''' is an English [[gold coin]] of the reign of [[James I of England|James I]], worth 25 [[shillings]] ({{frac|1|1|4}} [[pound sterling]]).<ref>{{Cite web |url=http://www.public-domain-content.com/books/discourse_coin_coinage/9.shtml |title=''A Discourse of Coin and Coinage'' |access-date=3 November 2005 |archive-date=22 November 2004 |archive-url=https://web.archive.org/web/20041122154646/http://www.public-domain-content.com/books/discourse_coin_coinage/9.shtml |url-status=dead }}</ref> The name of the coin comes from the Latin inscription surrounding the King's head on the obverse of the coin, <small>IACOBUS D G MAG BRIT FRA ET HI REX</small> ("James, by the grace of God, of Britain, France, and Ireland King").
[[Isaac Newton]] refers to the coin in a letter to [[John Locke]]:<ref>[http://www.gold.org/download/value/reserve_asset/history/monetary_history/vol1pdf/1698sep19.pdf Letter of Isaac Newton] dated September 19, 1698, to [[John Locke]], concerning the weight and fineness of various coins.</ref>
{{blockquote|The Jacobus piece coin'd for 20 shillings is the {{sic|hide=y|41|st}}: part of a pound Troy, and a Carolus 20s piece is of the same weight. But a broad Jacobus (as I find by weighing some of them) is the 38th part of a pound Troy.}}
These correspond to masses of 9.10 and 9.82 [[gram]]s respectively, making the broad Jacobus slightly heavier.
==References== {{Portal|Money}} {{reflist}} {{Coins of England}}
[[Category:Coins of England]] [[Category:English gold coins]]
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