A coin of Philip IV, PHILIP IV "THE FAIR" who reigned from 1285 to 1314 AD.
The obverse depicts a large Templar Cross: + PHILIPPVS. REX ; LÉGENDE EXTÉRIEURE : + BHDICTV: SIT: HOME: DHI: NRI: DEI: IHV. XPI, (Philip the king; blessed be the name of our Lord Jesus Christ)
The reverse of the coin displays a Châtel tournois topped with a croisette cutting the legend at 12 o'clock; outer border of twelve lilies in oves., the legend reads: TVRONVS (TRIANGLE) CIVIS. (City of Tours)
The coin has been made into a dress hook so it's classed as treasure, Theoretically it's a artefact not a coin,
In the late thirteenth and early fourteenth centuries a trend for coins fashioned into dress hooks became popular I use the term dress hook rather than brooch, as the attachments soldered onto surviving examples consist of a loop and hook. The loop is clearly intended to be sewn onto a garment with the hook used to secure part of an item of clothing to another. The choice of coins used show a marked preference for larger module pieces; initially these were Edward I’s groats but as the denomination was withdrawn from the English currency similar size gros from the continent were substituted and used instead. In a handful of cases pennies have been used. The method of conversion sees the cross side gilded (obverse on English coins, reverse on French coins) and the soldering of either a single or double piece loop and hook to the opposing face.