SPECIFICITIES OF THE MASONRY TECHNIQUE OF KYIVAN MONUMENTS OF THE XTH THE BEGINNING OF THE XIITH CENTURIES
Authors: Logvyn Natalia 
Published: April 2021

The material presented above concerns the research of the concealed course technique used in Kyivan monuments of the Xth the beginning of the XIIth centuries and its origin.
The concealed course technique presents the brickwork where the alternating brick courses are slightly recessed from the wall and covered by mortar, as a result, joints appear to be much thicker than they actually are.
The earliest known monument where the concealed course technique that occurs in the Desyatynna church in Kyiv completed in 996, as well as the two palaces of the Xth c. nearby. The recessed brick technique is also used in Kyivan monuments of the XIth the beginning of the XIIth centuries: the St. Sophia Cathedral, the Golden Gate, St. George’s Church, St. Michael’s Church of Vydubytsky Monastery, the Assumption Cathedral and the Holy Trinity Gate Church of Pechersky Monastery, St.Michael’s Cathedral of the Golden Domes and some other buildings. The Church of Our Savior at Berestove, completed in the first quarter of the XIIth century is the last known Kyivan monument with the concealed course technique. The following Kyivan monuments – the Church of Our Lady Pyrohoshcha (1130’s) and the St. Cyril’s Church (1140’s) have coursed brick masonry.
Apart from Kyiv the concealed course technique was used during the XIth - XIIth centuries in Chernihiv (the Cathedral of the Transfiguration), Pereyaslav (St. Michael’s Church), Novgorod (St. Sophia Cathedral and St. George’s Cathedral of St. George’s Monastery) and Polotsk (St. Sophia Cathedral).
Bricks used in Kyivan monuments have their side dimensions 27 to 36 cm with prevailed dimensions 27 to 36 cm. The thickness of bricks increased from 2.5 – 3 cm at the end of the Xth – the beginning of the XIth centuries to 3.5 – 4.5 cm at the end of the XIth – the beginning of the XIIth centuries. The width of mortar strips between protruding brick courses varies from 9 to 12 cm.
Walls in ancient Kyivan monuments were 1.1 to 1.3 meter thick. After the edifice was erected its outside and inside walls were covered with fine lime-and-ceramic plaster.

Brunov was the first scholar who noticed peculiar masonry technique used in Kyivan and several Byzantine monuments. He considered the concealed course technique first appeared in ancient Kyiv and then was adopted at Constantinople. Some other scholars (e.g. P. Rappoport and P. Vocotopoulos) agree that the technique is of Constantinopolitan origin in spite of the absence of the monuments built in concealed course technique, dating to the Xth c. The fact that no early dated examples have been found at Constantinople should be attributed to the lack of monuments to be dated between 920s, when the Myrelaion Church was erected and the middle of the XIth century when the monastery of St.George at Mangana was founded.

The oldest dated example of the concealed course technique known up to now in Constantinople is substructure of the St. George’s Church at Mangana. The other monument with the concealed course technique is the Panaghia Chalkeon Church in Salonika, dated by 1028 and is consequently earlier by approximately twenty years than the earliest dated examples of the technique in Constantinople. A lot of Byzantine monuments with the recessed brickwork dating back to the XIth – the XIIIth centuries could be found at Greece and Balkans.
It is obvious that the concealed course technique originated in Byzantium as a result of development of Roman concrete facing of coursed brick. The technique was widely used in Byzantine provinces where brick was prevailing building material. Evidently the technique was developed already at the Xth century or even earlier, before it was adopted by ancient Kyivan builders. It appeared that concealed course technique could not be undoubtedly considered the hallmark of Constantinople but a widely spread medieval building practice.