Dolium

A dolium (plural: dolia) is a large earthenware vase or vessel used in ancient Roman times for the fermentation of alcoholic beverages, as well as storage or transportation of goods. They are similar to kvevri, large Georgian vessels used to ferment wine.

The dolium was a large jug or container made of fired clay. Oval in shape, with a wide mouth and rim, it was much larger than the amphora, a similar pottery container. The dolium had no neck or handles and, in many cases, could measure up to six feet in height. Some dolia have a rounded body tapering into a flat bottom, while more frequently, dolia maintained a rounded bottom. They were lined with pitch or wax in order to contain or process liquids and solid foods. Some sources mention dolia holding up to 50 quadrantals, equivalent to 346.5 US gallons (1,312 litres). There was no standard size for dolia.

Much of what modern scholars know about the dolium comes from ancient Latin literature. Sources which address agriculture, significantly De agri cultura by Cato the Elder, Res rustica by Varro, Res rustica by Columella, and the Res rustica by Palladius, help us determine the size, appearance and purposes of the dolia. Because these sources deal with rural matters of the time, they also give scholars an insight into the life and culture of ancient Rome in addition to specific information about use of the dolium. Another noteworthy source is the Digest of Justinian I. It is a collection of quotations from earlier works of Roman jurists that discuss the importance of the integration of dolia in ancient Roman society. These sources, along with a variety of other less significant sources where dolia are only briefly mentioned, characterize the dolia as the largest type of earthenware vessel made by the Romans.

There is evidence to support the claim of many classical archaeologists that dolia were used exclusively on land for the processing and storage of foodstuffs. For instance, dolia were manufactured for the most part by travelling specialist potters or by workshops that were involved principally in production of architectural ceramics. Dolia were used in food production areas, such as farmhouses, and selling points like taverns and town warehouses. Dolia were also used in theatres for their acoustic qualities (presumably for special sound effects).

The two methods of storing dolia were to either bury them half way in the ground or standing under a roof. They were used to hold goods such as wine, grape husks, olive oil, amurca, wheat, and other common grains. Many dolia hold record amounts of 40-50 quadrantals (quadrantals being the general amount held in one amphora). Unlike the amphora, the dolium was not regarded as an accessory and sold along with the wine that it contained. Rather, dolia were fixed facilities not employed for the distribution of wine. Its major purpose was for the permanent storage capacity of goods.

However, dolia were also commonly used in conjunction with transport facilities such as merchant ships and temporary storage places like harbor warehouses. Surprisingly, given their construction, dolia were often used in overseas transport. Recent archaeological discoveries indicate two or three rows of dolia were sometimes positioned along the keel of a merchant ship, apparently cemented in place to prevent shifting with the ship's movement at sea. This technique allowed dolia to serve as fixed receptacles for the transport of wine. The high prices of dolia is evidence to indicate that their incorporation into maritime transportation represented a substantial investment of funds. Also, given their great weight and bulk, replacement must have represented both an inconvenience and an expense. Thus, extraordinary caution must have been employed when handling the dolia to preserve and maintain their useful life.

Ethnographic research indicates that in many cases dolia remained in use for several decades, and therefore, it seems plausible to suggest that dolia regularly remained in prime use for up to 20–30 years and perhaps longer.

While the mystery of the dolia in relation to maritime commerce is still being researched, archaeologists have substantial evidence from shipwrecks to support its significant, yet short role. One of the most striking evidences of the use of dolia in the commerce of food supplies is their presence on board Roman merchant ships. There have been at least seven shipwrecks discovered carrying dolia, dating between the 1st century BC and the 3rd century AD. Three of the most interesting and identifiable shipwrecks that lend themselves to study of dolia are the Diano Marina, the Petit Congloue, and the La Giraglia shipwrecks.