An unusual discovery

Archaeological research and radiocarbon dating show that the builders began using iron brackets in the early stages of the cathedral’s construction. in the early 1160s. Thus, Notre Dame Cathedral is the earliest known Gothic cathedral to have applied this technological solution.

Earlier structures, such as the cathedral at Soissons where anchor rods were used, and the cathedrals at Bourges and Chartres, whose construction began at the end of the 12th century, were not built using iron reinforcements.

Metal elements in the structure of Notre Dame de Paris

Maxime L’Heritier of the National Center for Scientific Research, in collaboration with researchers from the UAE and France, discovered that staples from Nord-Dame de Paris were forged from several pieces of iron. This technique was used in fittings from different parts of the cathedral, which was built with a difference of 40-50 years.

The researchers found that the sources of this rebar could only be distinguished by metallographic and microscopic analysis.

Seams on staples can only be detected by microscopic analysis / Photo: PLoS ONE

What scientists learned about the equipment in the cathedral

The basic composition of the rebar revealed at least six different raw material sources, none of which were dominant. While in the early stages of construction (mid to late 12th century), only one raw material source was used for staples, while in the early 13th century iron came from at least five other places.

The discovery sheds new light on the construction of one of France’s most iconic monuments. It showcases the creativity and skill of medieval architects and builders who used innovative technologies to construct such impressive structures. This information will also help in the rebuilding of Notre Dame Cathedral, which has become a symbol of hope and endurance.

A little about the history of Notre Dame de Paris

Notre Dame Cathedral was built between 1163 and 1345 on the island of Cite, in the very center of the French capital. The building is a Gothic five-nave basilica with a short transept, a choir and a chapel crown. The facade is decorated with sculptures, including scenes from the life of the Mother of God and the Last Judgment. In the 17th and 18th centuries, the interior and façade of the cathedral was significantly rebuilt. In the middle of the 19th century, a 96-meter oak tower was built, decorated with bronze statues of the apostles and heralds.

In April 2019, a devastating fire broke out in the cathedral, causing significant damage to the building. During the reconstruction process, scientists had the opportunity to examine the cathedral and its various sections more closely. This is how scientists discovered that iron staples were widely used to fix stone blocks to the walls and vaults of the temple.