The use of marine molluskan shells for Roman glass and local raw glass production in the Eifel area (western Germany).

Relatively high strontium concentrations and their isotopic composition in Roman glass of the Imperial period indicate the general use of shells as carbonate raw material. Lead, iron, and barium concentrations and lead isotopes of glass of the late fourth century from Hambach and Gellep (western Germany) are conformable with the use of glass sand from Eifel rivers. Each of three pairs of six simultaneously operating Roman glasshouses in the Hambach area made its own raw glass from different quartz sands.