Tabby (cement)

Tabby is a type of concrete made by burning oyster shells to create lime, then mixing it with water, sand, ash and broken oyster shells. Tabby was used by early Spanish settlers in present-day North Carolina and Florida, then by English colonists primarily in coastal South Carolina and Georgia.

Revivals in the use of tabby spread northward and continued into the early 19th century. Tabby was normally protected with a coating of plaster or stucco.

Tabby's origin is uncertain. There is evidence that North African Moors brought a predecessor form of tabby to Spain when they invaded that kingdom: a form of tabby is used in Morocco today and some tabby structures survive in Spain, though in both instances the aggregate is granite, not oyster shells.

It is likely that 16th-century Spanish explorers first brought tabby (which appears as "tabee", "tapis", "tappy" and "tapia" in early documents) to the coast of Florida in the sixteenth century.Tapia is Spanish for "mud wall" and Arabic tabbi means a mixture of mortar and lime or African tabi. In fact, the mortar used to chink the earliest cabins in this area was a mixture of mud and Spanish moss.

Some researchers believe that English colonists developed their own process independently of the Spanish.

James Oglethorpe is credited with introducing "Oglethorpe tabby" into Georgia after seeing Spanish forts in Florida and encouraging its use, using it himself for his house near Fort Frederica. Later Thomas Spalding, who had grown up in Oglethorpe's house, led a tabby revival in the second quarter of the 19th century sometimes referred to as "Spalding tabby". Another revival occurred with the development of Jekyll Island in the 1880s.

Limestone to make building lime was not available to early settlers so lime was imported or made from oyster shells. Shell middens along the coast proved to be a supply of shells to make tabby which diffused from two primary centers or hearths: one at Saint Augustine, Florida, and the other at Beaufort, South Carolina.

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