This extraordinary Neapolitan Baroque masterpiece was built between 1672 and 1691 for the church of Santa Teresa degli Studi. The altar was moved to the Royal Palace in 1808, following the suppression of ecclesiastical bodies - by the French government of Giuseppe Bonaparte - with which the religious property was confiscated by the State.

The altar is characterized by gilded copper ornaments with precious semiprecious stone covering (agate, jasper, lapis lazuli, amethyst, onyx, malachite), set to create perspective designs. In the frontal (the central panel) and in the lateral doors the architectural arrangement of the whole creates the image of a temple with pillars, niches and balustrades. In the vanishing point of the scenographic central perspective, Santa Teresa is represented, to whom the altar is dedicated.

In the ciborium there is a panel of semi-precious stones inlaid on a black Belgian background, made by the Opificio delle Pietre Dure in Florence in 1772, a gift from Cosimo III to the Teresian Fathers.

The altar was saved from the bombs of 14 August 1943 thanks to an emergency protection put in place during the war. A structure of wooden boards completely covered with sandbags managed to protect the work when it was hit by the collapse of the vault of the chapel.