Romanesque-byzantine domes and their gilded mosaics — Notre-Dame de la Garde by Jorge Lascar

Notre-Dame de la Garde (Our Lady of the Guard), in French for Marseille’s citizens “la bonne mère” (the good (holy) mother), is a Catholic basilica in Marseille, France, and the city's best-known symbol. The nave's interior is 32.7 m long and 14 m wide. Each side chapel measures 3.8 m by 5.4 m. The interior is decorated with 1,200 m2 (13,000 sq ft) of mosaics as well as alternating red and white marble columns and pilasters. Espérandieu wanted a subtle red that would harmonise with the mosaics and not clash too much with the whiteness of the Carrara marble. Jules Cantini, the marble worker, discovered such a red marble with yellow and white veins in the commune of La Celle near Brignoles, Var. For parts higher up, plaster—i.e. reconstituted marble—was used. The mosaics were created between 1886 and 1892 by the Mora company from Nimes. The tesserae came from Venice and were manufactured by craftsmen at the height of their art. Each panel comprises nearly ten thousand tesserae per square metre, which means that the basilica contains approximately 12 million small squares of 1 to 2 cm2 (0.31 sq in). The floors are covered with approximately 380 m2 (4,100 sq ft) of Roman mosaics with geometric patterns [Wikipedia.org]