The advancement of the construction of the Chapel was strongly promoted in 1818 by the grand duke Ferdinand III Hapsburg Lorraine. The decorations of the tambour and the dome, the floor and the altar had yet to be made in order to complete the mausoleum. Here you can see the project of the altar designed in 1860, where a panel with a laurel wreath and another one with a laurel and olive wreath are clearly visible. The laurel and olive wreath was made in 1849, according to the oil painting by Giovan Battista Giorgi, datable to 1820-1830, that you can see next to the panel. The background was made with red porphyry; the leaves and the ribbon were made with chalcedony, according to the neoclassical style.
