In front of the East door of the Dome of the Rock lies a small edifice, the Dome of the Chain (Qubbet es Silsileh), composed of a colonnade with Byzantine elements including, in its eleven-sided polygonal plan, a hexagonal portico which supports a drum and a dome. It is the Beit el Mal, or treasure, built by Abd-el-Malik.

The space between the two cupolas, in the drum, according to a likely hypothesis constituted the place where the treasure was laid. The building is of the same type as the treasures of the Omeyyads mosque in Damascus, or of the Grand Mosques of Homs and Hama. In order to render this place inviolable, it was endowed with a sacred character by means of relating it to the traditions connected with the Chain of Judgment hung by Solomon at the tribunal of David. The word also has a mystical character since it represents the invisible link between the believer and Allah.