The chapel, integrated in the estate of Santa Maria or Quinta do Duque (because it belonged to the Dukes of Cadaval), is dedicated to Nossa Senhora da Graça (Our Lady of Grace), for the property belonged to the lodge of Santa Maria or Nossa Senhora da Graça, since the 15^th century, in whose headquarters was also built a church of the same religious invocation.
Its structure is originally from the 17^th century, but it might have been preceded by a 16^th century building, later converted into a sacristy.
The chapel is preceded by a porch supported by three columns of stone, Tuscan in style, one of them added by fragment of spiralled shaft with Manueline style ornaments. In it are benches of recent construction lined with 17^th century tiles, acquired in antiques, and a cross also in tiles. The chapel has a stone portal and quadrangular nave, covered by irregular ribbed vaults and with ashlars of tiles in the four façades. These, in blue and white, from the period of portuguese King D. João V, constitute eight panels that represent scenes of tales of monks and hermits of the desert, but were only placed in the 20^th century’s 1960s, coming from an unknown place.
The main chapel is preceded by a granite portal with lintel. It has a rectangular plan and is covered by a half-barrel vault with caissons in relief with a large stucco flower in the middle. The façades are fully lined with polychrome tiles, just like the altar front lined with typical middle 17^th century azulejos. The main altarpiece is elaborated in gilded woodcarving of baroque style. The titular image, in terracotta, is Nossa Senhora da Graça (Our Lady of Graces) and was made in 1773 by a friar from the convent of São Francisco of Viana.
The sacristy has a square plan, covered by a half spherical dome and covered with tiles.
It has a bell tower in ornate masonry.
 

REFERENCES
ESPANCA, Túlio, Inventário Artístico de Portugal: Distrito de Évora: Concelhos de Alandroal, Borba, Mourão, Portel, Redondo, Reguengos de Monsaraz, Viana do Alentejo e Vila Viçosa, Lisboa, Academia Nacional de Belas-Artes, 1978,Tomo IX, Vol. 1.
http://rotadofresco.inwebonline.net