It was probably just before the Roman Conquest that the hoard was buried within the Gallic enclosure. Protected for centuries by an embankment, its 545 electrum (gold and silver alloy) coins were scattered over 200 m2 by recent agricultural activity, but are nonetheless very well preserved.
The Laniscat hoard consists of 58 stater coins and 487 quarter stater coins. All of them were minted by the Osismii people. This is the largest hoard ever found in Celtic Brittany: 254 coins were found at Kersaint-Plabennec in 1903 (Finistère), 254 at Guingamp in 1934 (Côtes-d'Armor), 184 at Perros-Guirrec in 1933 (Côtes-d'Armor), 53 at Poullaouen in 1853 (Finistère)... This new find includes rare coins and hitherto unknown variants, such as Carantec type staters, of which only six were formerly known. On the obverse face, these coins have a human head on the left with hair arranged in thick strands. A double, beaded cord encircles the hair and has a small head at each extremity. In front of the face there is a wild boar. On the reverse side, a cavalier sits on a horse which does not have a human head to the left. In his right hand he brandishes a lance and in the left hand he holds a shield. In front of the horse there is a floral motif. Under the horse, there is a wild boar motif.
The metal composition of the coins, a triple alloy of gold, silver and a high proportion of copper, confirms the late date of the deposit, about 75-50 BC.
The importance of this hoard is emphasized by its archaeological context. It is a considerable sum of money for the period and provides information on the status of the site and its occupants. It allows us to reconsider the role and importance of the Osismii people on the Brittany peninsula.

Pytheas of Marseille, a Greek navigator who left Marseille around 300 BC for the Isle of Brittany (now Great Britain), mentioned the presence of the Ostimioi, a people located on the extremity of a peninsula that reached far into the Ocean. According to Léon Fleuriot, this term meant "the most distant", or "the Finisterians", a fitting name for these people living at the extremity of the continent. A few centuries later, we find them again in Latin texts under the name of Osismii.
Julius Caesar mentioned this people, who were allied with the Venitis during the Gallic Wars. It was long thought that the Osismii, who occupied the extremity of the Brittany peninsula, lived under the rule of their powerful neighbours in Morbihan. Recent archaeological data however now show that the city-state of the Osismii predominated and controlled the maritime traffic between the Atlantic and the English Channel, as well as precious metal deposits. It commanded a vast territory, including the Finistère, the western Morbihan and the Côtes-d'Armor.
The discovery of the Laniscat Osismii hoard will help archaeologists to more precisely define the eastern borders of this city-state, structured around two major fortified settlements, the oppida of Huelgoat and Paule, and a series of secondary settlements, such as Quimper and Douarnenez.