Bulla (seal)

A Bulla (, plural bullae) is an inscribed clay or soft metal (such as lead or tin) or bitumen or wax token used in commercial and legal documentation as a form of identification and for tamper-proofing whatever is attached to it (or, in the historical form, contained in it). In their oldest attested form, as used in the ancient Near and Middle East of the 8th millennium BCE onwards, bullae were hollow ball-like clay envelopes that contained other smaller tokens that identified the quantity and types of goods being recorded. In this form, bullae represent one of the earliest forms of specialization in the ancient world, and likely required skill to create. From about the 4th millennium BCE onwards, as communications on papyrus and parchment became widespread, bullae evolved into simpler tokens that were were attached to the documents with cord, and impressed with a unique sign (i.e. seal) to provide the same kind of authoritative identification and for tamper-proofing. Bullae are still occasionally attached to documents for these purposes (cf. papal bull).

During the period 8,000–7,500 BCE, the Sumerian agriculturalists needed a way to keep records of their animals and goods. Small clay tokens were formed and shaped by the palms to represent certain animals and goods.

Clay tokens allowed for agriculturalists to keep track of animals and food that had been traded, stored, and/or sold. Because grain production became such a major part of life, they needed to store their extra grain in shared facilities and account for their food. This clay token system went unchanged for about 4,000 years until the tokens started to become more elaborate in appearance. The tokens were similar in size, material, and color but the markings had more of a variety of shapes. As the growth of goods being produced grew and the exchanging of goods became more common, changes to tokens were made to keep up with the growth.

Transactions for trading needed to be accounted for efficiently, so the clay tokens were placed in a clay ball (bulla) to keep the tokens together. This helped with dishonesty and kept all the tokens together. In order to account for the tokens, the bulla would have to be crushed to reveal their content. This introduced the idea of impressing the token onto the wet bulla before it dried,to insure trust that the tokens hadn't been tampered with and for anyone to know what exactly was in the bulla without having to break it. Eventually seals were impressed into the clay alongside of the impression of the tokens. Each party had its own unique seal to identify them. Seals would not only identify individuals, but it would also identify their office.

As the clay tokens and bulla became difficult to store and handle, impressing the tokens on clay tablets became increasingly popular. Clay tablets were easier to store, neater to write on, and less likely to be lost. Impressing the tokens on clay tablets was more efficient but using a stylus to inscribe the impression on the clay tablet was shown to be even more efficient and much faster for the scribes. Around 3,100 BCE signs expressing numerical value began. By now, clay tokens became obsolete, a thing of the past.

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