The public building
The Tuynhuys building in Cape Town, South Africa is the most visited office of the president of South Africa. Reconstructed in 1968, the main material used in the building was from the Tristan da Cunha Island. The interior of the building was fabricated with limestone blocks from this island in the Atlantic Ocean. This paper describes the type of mineral used in the construction of the Tuynhuys building, where it came from, and a brief history of the mineral.
Mineral used: Limestone
The Tuynhuys building’s interior was constructed with limestone blocks from the Tristan da Cunha Island. The limestone blocks were handcrafted from the island and transported to South Africa. This particular mineral is called the Trenton limestone. It was created from accumulation of aragonite and mineral calcite from marine organisms.
The main marine organisms that formed the Tristan da Cunha limestone were foraminifera and corals. Within the terrain of the Tristan da Cunha Island, limestone makes up 30% of its sedimentary rocks. Unlike other limestone rocks, the Tristan da Cunha limestone is very stable and grey in color (Marshak 49).
Source of the limestone
The limestone used in the interior finishing of the Tuynhuys building came from the Tristan da Cunha Island. The islands that neighbor Tristan are Stoltenhoff Island with an area of 0.1 square kilometers, Middle Island with an area of 0.1 square kilometers, Nightingale Island with an area of 3.4 square kilometers, and Inaccessible Island with an area of 14 square kilometers.
Out of the five islands in that group, Tristan da Cunha is the largest and it covers an area of 113 square kilometers. In most cases, Gough is not considered as part of the chain of island because it is located several kilometers away from the group. The location of Tristan da Cunha is almost equidistant from Cape Town (South Africa) in the continent of Africa, and Rio de Janeiro (Brazil) and Buenos Aires, Argentina in the continent of South America (Christophersen 702).
The Island is approximately 1,800 miles from South Africa and approximately 2,150 miles from Brazil. Further, the Tristan Island is circular in shape with a diameter of 10 kilometers. This island has rich deposits of limestone in the form of grey sedimentary rocks.
The limestone from this Island is believed to have been formed several centuries ago as a result of deposits of the decaying remains of foraminifera and corals. These organisms were washed ashore onto the island by tides from the Atlantic Ocean. Over the years, the accumulated deposits turned into limestone.
Unusual fact/story about the island
The Tristan da Cunha is mainly covered with the moss and fern. The vegetation cover on the Island is made up of a number of widespread species. These species are widely distributed and they have also been found in other regions such as the southern areas of the Pacific and Atlantic oceans.
The volcanic activities in the island Tristan da Cunha and the entire Mid – Atlantic Ridge played a significant role in the cracking of the borders of South Atlantic Ocean. The activities led to the creation of the classical plume theory. The volcanic activities gave rise to the Walvis Ridge and Rio Grande Rise. It is rumored that the volcanic activities were responsible for strengthening the limestone found in this island (Irene Schaffer’s Website 1).
Christophersen, Erling. “Tristan da Cunha the Lonely Isle”. Geographical Review. 31.4 (1941): 697-710. Print.
Irene Schaffer’s Website 2008, Tristan da Cunha.
Marshak, Stephen. Essentials of Geology, New York, NY: W. W. Norton, 2013. Print.