Pyrochlore crystal (2018-08-27) by Leonardo MirandaMM Gerdau - Museu das Minas e do Metal
The month of March 2023 celebrates one of the greatest achievements of brazilian Geosciences: 70 years ago, Niobium (metallic chemical element, symbol Nb) was discovered in the city of Araxá (Minas Gerais state), by the geoscientist and professor Djalma Guimarães.
Through this story, which took place in 1953, worthy of a best-selling investigation, with characters and narratives involved in the search for radioactive minerals during the post-war period, MM Gerdau presents unpublished details about this discovery.
The story of pyrochlore and the discovery of the largest deposit, economically viable, of this mineral that contains enormous amounts of niobium.
Periodic Table - Niobium (2023-03-10) by Lucas D'AmbrosioMM Gerdau - Museu das Minas e do Metal
Niobium: present and future
Periodic Table, of the permanent exhibition, on the third floor (Metal Floor) of MM Gerdau - Museum of Mines and Metal. Niobium (Nb) the element of atomic number (Z) = 41.
Most of the chemical elements in the Periodic Table are unfamiliar or we do not know the applications of most of them. However, niobium, which is scarce in other countries and has large deposits in Minas Gerais, Brazil, could be the key to a large number of new technologies.
Image of the JK Bridge (in Brasília, Brazil) and bike (MM Gerdau) - both made of light steel-niobium alloy, battery created in partnership with CBMM and coin in silver-niobium from the Austrian Mint. Niobium finds applications in civil construction, production of vehicles, and can be colored and be part of coins, in addition to being promising as a superconductor and being part of batteries.
Pyrochlore ore (2018-09-11) by Andrea FerreiraMM Gerdau - Museu das Minas e do Metal
The abundance of niobium in Minas Gerais and Brazil make it possible to supply a large part of the international market and practically the entire Brazilian market, where science is looking for different applications for its metallic form or chemical compounds.
Pyrochlore ore (2018-08-27) by Leonardo MirandaMM Gerdau - Museu das Minas e do Metal
This deposit of niobium was discovered in 1953 after a meticulous investigation that divided teams in the field and in the laboratory, working together, and generated enormous national attention.
Since its discovery, CBMM and Codemig have explored the pyrochlore deposit, whose economic advantage is the lack of Ta, which makes it difficult to separate Nb and increases the final product value.
Full page of Jornal Correio da Manhã RJ on March 13, 1953.
The news of the discovery exalted the person responsible for the discovery, the geologist Djalma Guimarães (1894 - 1973) who worked at the Institute of Industrial Technology of Minas Gerais.
Detail of journal news (1953-03-12) by Correio da Manhã and Hemeroteca Digital - Biblioteca NacionalMM Gerdau - Museu das Minas e do Metal
The Institute of Industrial Technology of Minas Gerais - ITI. It was an industrial certification and research department that served the Government of Minas Gerais since 1944, when it was founded and linked to the Ministry of Agriculture. In the ITI building - which still exists at Rua da Bahia 54, Belo Horizonte (MG), several scientists worked who gained prominence in the discovery of various minerals and their deposits, as in the case of Araxá’s Pyrochlore.
The 'Sector of Geology and Mines' was led by Djalma Guimarães who had other great scientists such as the brothers Cláudio and Cordélia Vieira Dutra and Fernando Peixoto who were responsible for chemical and spectroscopic analysis for the discovery of the element in minerals collected in the district of Barreiro, south of the urban center of Araxá, collected by Antônio B. Ottoni (geologist) in March 1953.
Cláudio Vieira Dutra and his Wife by Cláudio Vieira DutraMM Gerdau - Museu das Minas e do Metal
Cláudio Vieira Dutra and his wife.
Cornélia Vieira DutraMM Gerdau - Museu das Minas e do Metal
Córnelia Vieira Dutra, at ITI, in Belo Horizonte, Brazil.
Borehole drilling in Araxá, Minas Gerais.MM Gerdau - Museu das Minas e do Metal
Photos by Djalma Guimarães and Cláudio Vieira Dutra, plus Cornélia Vieira Dutra at ITI and A. B. Ottoni at Araxá. In addition to Djalma Guimarães, scientists such Antônio Ottoni (wearing a hat in the last photo) were essential in the discovery of niobium.
Mineraldrilling profileMM Gerdau - Museu das Minas e do Metal
Sketch that represent the drillings in the soil and the spectrum, that indicated the presence of niobium in the samples.
UV Spectrum (1953-03-10) by Cláudio Vieira DutraMM Gerdau - Museu das Minas e do Metal
The work was divided into field and laboratory. Identification of Niobium from Araxá/MG was done for the first time on March 10, 1953 Donated on 03-10-03, by Chemist Cláudio Dutra, who 60 years ago interpreted this spectrogram.
Araxá's niobium "birth certificate"
Unpublished manuscript by Djalma Guimarães describing the process of evaluating the deposit and the spectrum that determines the presence of niobium in the samples.
Given the sensitive radioactivity of the apatite-rich rock that occurs in Barreiro, we decided to take the initiative to carry out a careful examination of the southern area of the Grande Hotel. For that, we asked engineer A. B. Ottoni to go through that area with a Geiger counter and collect samples at the points of strongest radioactivity. The result was encouraging and prospecting for the deposit was recommended to CNPq (National Council for Scientific and Technological Development).
Manuscript prepared by Djalma Guimarães, containing notes regarding the composition of pyrochlore, for the “Report on preliminary prospecting in Barreiro, Araxá, Minas Gerais”.
Geological Map of Araxá, Brazil.MM Gerdau - Museu das Minas e do Metal
Geological map of the Araxá's region (MG)
The work by Guimarães and ITI also revealed a deposit of apatite, used as a fertilizer and, like niobium and radioactive elements, strategic to Brazil in the post-World War II period.
Scientists photograph by Arquivo Público MineiroMM Gerdau - Museu das Minas e do Metal
Group of scientists at the entrance of the Grande Hotel
The radioactivity in Araxá caught the attention of Russian scientists in 1947 who came to follow the total solar eclipse that happened in and this news circulated when the Cold War was starting.
Documentary: Memories of Mines