In the oppidum of Viguera (La Rioja, Northern Spain) a large number of clipped and trimmed bronze coins have been found. Most of the specimens discovered were original AE3 coins, struck throughout the 4th century but converted into AE4 at an uncertain date. A careful examination of these coins shows there are calculated ranges every 0.20 g. This phenomenon suggests that whoever was installed at the oppidum wanted a suitable array of small bronze fractions for a short period of time. In all probability the coins were altered during the first two decades of the 5th century. We discuss in our presentation how clipped siliquae and clipped and trimmed bronze coins should be studied in the West as a parallel phenomenon.