Lime preparation in ancient Roman architectural and marine mortars

Author(s): Marie Jackson; Gabriele Vola

Year: 2015


Romans prepared lime for the volcanic ash mortars of conglomeratic concretes using methods (Vitruvius, de Architectura 5.1.2-3) that are reflected in modern Italian lime industry terminology. In mortars of architectural concretes in Rome (1st C BCE–3rd C CE) builders mixed quicklime with freshwater to form stiff putty (grasello di calce) and then incorporated moistened scoriaceous ash, shown by an experimental reproduction. Pure calcite in unburnt particles (incotti) suggests pre-orogenic Jurassic-Cretaceous limestone of the Monti Sabini 30km northeast of Rome, rather than syn- and post-orogenic Cenozoic carbonate deposits with detrital silicate minerals. High calcium lime (94 wt% CaO) was likely calcined at the quarry; no marine limestone aggregate occurs in the concretes. In mortars of maritime harbor concretes (1st C BCE–2nd C CE) drilled by ROMACONS, builders used fine sand- to gravel-sized lime (zolle or greggio di calce) mainly calcined from local limestone, with high calcium compositions (Portus, Pozzuoli Bay), mixed calcic and dolomitic compositions (Cosa, Anzio, Egnazia, Caesarea, Alexandria) and, rarely, argillaceous compositions (Chersonessos). The lime was likely aged in freshwater (calce spenta e maturata), mixed in a trough with pumiceous ash, and submerged in submarine forms. Carbonate rock is the predominant aggregate of eastern Mediterranean harbor concretes.

SAA 2015 abstracts made available in tDAR courtesy of the Society for American Archaeology and Center for Digital Antiquity Collaborative Program to improve digital data in archaeology. If you are the author of this presentation you may upload your paper, poster, presentation, or associated data (up to 3 files/30MB) for free. Please visit for instructions and more information.

Cite this Record

Lime preparation in ancient Roman architectural and marine mortars. Marie Jackson, Gabriele Vola. Presented at The 80th Annual Meeting of the Society for American Archaeology, San Francisco, California. 2015 ( tDAR id: 395475)


Geographic Keywords

Spatial Coverage

min long: -11.074; min lat: 37.44 ; max long: 50.098; max lat: 70.845 ;