Aventicum (modern Avenches), on the Rhine in Switzerland, was a glassworking center that, like Octodurus, imported bulk glass ingots from afar. To supplement these supplies, however, glassworkers there re-melted loads of broken glassware (cullet) that periodically were carted in from the local towns and military camps. The workshop's own immediate debris was recycled as well. Presumably the end-product again was some kind of ingot. But its color probably was limited to green—with hues ranging anywhere from light and blue-tinged to blackened and murky—and very much an arbitrary blend of whatever went into the melting pot on any particular day.
Provincial glassmakers were in the market for cullet because it saved them from having to buy expensive fresh ingredients from afar. They also were surely aware that finely crushed cullet, when mixed into a batch of valuable raw materials, would act as kernels for its fusion, and so encourage a uniform consistency in the glass stock. Cullet from colored monochrome wares also was sold directly to mosaic-makers, for use in the decoration of the meeting rooms of larger provincial cities or of the spas of luxurious villas in the neighboring countryside.