Gemology of Emeralds from Tauá, Brazil

Autores

  • Isaac Gomes de Oliveira Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP https://orcid.org/0000-0002-3874-4238
  • Laryssa de Sousa Carneiro Department of Geology and Natural Resources, Institute of Geosciences, University of Campinas, 250, Carlos Gomes St., Campinas, SP, Brazil. https://orcid.org/0000-0003-3448-3322
  • Alina de Oliveira Cunha Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP https://orcid.org/0009-0000-7690-8013
  • Conceição Regina Fernandes Alves Federal University of Ceará, Science Center, Department of Chemistry – Avenue Mister Hull, s/n – Pici University Campus, Block 932 – Fortaleza, CE – CEP 60020-181, Brazil. https://orcid.org/0000-0001-5769-4910
  • Gabriel Czar dos Santos Eng química da Federal Technological University of Paraná, Department of Chemical Engineering - Avenue Seven September, 3165 Rebouças, Block H - Curitiba PR, CEP 80230-901, Brazil https://orcid.org/0009-0006-1998-3096
  • Lee Andrew Groat The University of British Columbia, Department of Earth, Ocean and Atmospheric Sciences, Faculty of Science, 2020 – 2207 Main Mall, Vancouver, BC, Canada. https://orcid.org/0000-0003-0108-0842
  • Lucilene dos Santos Federal University of Ceará, Science Center, Department of Chemistry – Avenue Mister Hull, s/n – Pici University Campus, Block 932 – Fortaleza, CE – CEP 60020-181, Brazil. https://orcid.org/0000-0002-8304-6869
  • Carlos William de Araújo Paschoal Federal University of Ceará, Science Center, Department of Physics – Avenue Mister Hull, s/n – Pici University Campus, Block 928 – Fortaleza, CE – CEP 60.455-760, Brazil. https://orcid.org/0000-0001-9055-387X
  • Tereza Falcão de Oliveira Neri Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP https://orcid.org/0009-0002-6995-6521

DOI:

https://doi.org/10.11137/1982-3908_2025_48_67822

Palavras-chave:

Gemological beryl, Geochemical characteristics, Ceará gems

Resumo

In Brazilian territory many occurrences do not have their gemological and optical properties documented or made public. This research aimed to analyze the mineralogical and gemological aspects of emeralds from the city of Tauá (Brazil), utilizing gemological instruments such as a refractometer, dichroscope, spectroscope, polariscope, hydrostatic balance, ultraviolet lamp, and gemological microscope. The examined emeralds exhibit typical features found in emeralds worldwide, except for an above-average birefringence, similar to certain beryls from the state of Ceará. This highlights the significance of gemological characterization not only at the regional levels but also on a localized scale. Additionally, studying occurrences in varied geological settings is essential, as the formation environment influences mineral properties.

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Biografia do Autor

Isaac Gomes de Oliveira, Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP

He holds a degree in Geology from the Federal University of Ceará (2018), a master's degree in Geology (Gemology, Mineralogy) from the Federal University of Ceará (2020), Inventor (2022) and a doctorate (PhD) in Geology (Gemology, Mineralogy and Geochemistry) from the same institution (2024). He is interested in the areas of gemology and mineralogy. Since August 2015, he has been a member of the TN gemology laboratory, working as a collaborator in research, extension and teaching; he was a volunteer monitor in the introduction to gemology discipline (2015-2019), and he was also a volunteer monitor in optical mineralogy (2015-2018). He works in the following areas: gemology (with emphasis on tourmalines, aquamarines, garnets, amethysts, rubies and emeralds), optical mineralogy, mineralogy, geochemistry, crystal chemistry and magnetism.

Laryssa de Sousa Carneiro, Department of Geology and Natural Resources, Institute of Geosciences, University of Campinas, 250, Carlos Gomes St., Campinas, SP, Brazil.

Geologist (2018) from the Federal University of Ceará (UFC), master (2021) in Geosciences and PhD (2025) in Sciences in the area of ​​Geology and Natural Resources from the State University of Campinas (UNICAMP). She has experience in the area of ​​Crustal Evolution and Metallogenesis, with emphasis on lithogeochemistry, isotopic geochemistry and geochronology. In her Final Course Work she carried out geological mapping, in addition to characterization and mapping of hydrothermal alteration zones associated with occurrences of hematite and sulfides in the context of IOCG-type deposits in the Pio IX region (PI). In her master's thesis she developed research with geochemical analysis and characterization and identification of prospective vectors in alteration and mineralization zones of Cu deposits in the Carajás Mineral Province (IOCG and granite-related Cu-Au). She worked as a volunteer monitor for Leapfrog Geo/Edge and received training from Seequent as an associate student. From his doctorate to the present, he has been developing research on geochronology and isotopic geochemistry of Paleo-Mesoarchean magmatic rocks in the southwest of the Carajás Province, and on hydrothermal and isotopic characterization (geochronology, stable and radiogenic isotopes) of copper deposits analogous to Mesoarchean porphyry Cu deposits and Neoarchean Cu-Ni deposits associated with the regional IOCG system of the Carajás Province.

Alina de Oliveira Cunha, Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP

geologist and mining technician, completing a master's degree in Geochemistry of Ornamental Rocks. During my academic career, I worked as a teaching fellow in subjects such as Mineralogy, Crystal Chemistry and Optical Mineralogy, in addition to participating in research projects focused on the characterization of dolomitic limestones and the geochemical evaluation of oil and gas source rocks in the deep portion of the Potiguar Basin, using organic chemistry techniques. I served as vice president of the American Association of Petroleum Geologists (AAPG).

I currently work professionally with processing, interpretation and preparation of geophysical reports, with applications focused on engineering and mining.

Conceição Regina Fernandes Alves, Federal University of Ceará, Science Center, Department of Chemistry – Avenue Mister Hull, s/n – Pici University Campus, Block 932 – Fortaleza, CE – CEP 60020-181, Brazil.

Bachelor's degree in Chemistry from the Federal University of Ceará (UFC, 2019). Master's degree in Chemistry from the Federal University of Ceará (UFC, 2022). Studies the development of hierarchically structured zeolitic materials for environmental applications.

Gabriel Czar dos Santos, Eng química da Federal Technological University of Paraná, Department of Chemical Engineering - Avenue Seven September, 3165 Rebouças, Block H - Curitiba PR, CEP 80230-901, Brazil

Graduated in Chemical Engineering from the Federal University of Technology – Paraná (UTFPR), in the Department of Chemical Engineering. He has professional experience in the banking sector, having worked at Banco Bradesco, where he developed skills in financial analysis, customer service, and management of administrative processes. Additionally, he complemented his education with a degree in Business Administration, broadening his strategic vision and business management skills.

He also participated in the Junior Enterprise of Chemical Engineering, where he played an active role in project development, consulting, and innovation activities, gaining practical and leadership experience in both the corporate and academic environments.

Lee Andrew Groat, The University of British Columbia, Department of Earth, Ocean and Atmospheric Sciences, Faculty of Science, 2020 – 2207 Main Mall, Vancouver, BC, Canada.

Lee A. Groat earned a Ph.D. in geology from the University of Manitoba in 1988. He has been@the University of British Columbia since 1989, where he is now a professor of Earth and ocean sciences and director of the Integrated Sciences program. In 1999 he was awarded the Young Scientist Medal of the Mineralogical Association of Canada and in 2002 he was awarded a Killam Prize for Excellence in Teaching. He is a past editor of American Mineralogist and current coeditor of Canadian Mineralogist. In 2009 the new mineral groatite, NaCaMn2+2(PO4)[PO3(OH)] 2, was named in his honor. He is on the board of directors and an adviser to several Canadian mineral exploration companies, and co-runs a geological consulting company.

Lucilene dos Santos, Federal University of Ceará, Science Center, Department of Chemistry – Avenue Mister Hull, s/n – Pici University Campus, Block 932 – Fortaleza, CE – CEP 60020-181, Brazil.

Possui Graduação em Geologia (2011), Mestrado em Geociências na área de concentração Petrologia e Geoquímica (2013), Doutorado (2017) em Petrologia e Evolução Crustal com uma tese sobre os processos formadores de magmas (Análise e Modelamento de Dados Geoquímicos, Isotópicos e Geocronológicos. Uma aplicação para tipologia de magmatismo, restrição do ambiente geodinâmico e evolução do sistema manto-crosta) pela Universidade Federal de Pernambuco. Estágio no Laboratório de Geoquímica Isotópica - Laser Ablation-ICP-MS (U-Pb, Elementos Traço em Zircão e Titanita) da Universidade Federal de Ouro Preto (11/2015 e 4/2016). Foi Professora de Mineralogia e Cristalografia para os Cursos de Engenharia de Materiais e Geologia, e Mineralogia Aplicada à Mineração para Engenharia de Minas (UFPE - 2014 a 2016). Atuando na área de Geologia: Mapeamento Geológico, Química Mineral, Geoquímica de Rocha Total, Geoquímica Isotópica e Geocronologia; Caracterização Cristaloquímica e Cristalofísica de Minerais - Aplicação industrial e materiais multifuncionais (sustentáveis). Pesquisas em desenvolvimento com grafita (produção de grafeno), quartzo de alta pureza e tantalatos da Província Borborema, NE do Brasil. Professora Adjunta, Vice-coordenadora do Curso de Geologia/UFC, Coordenadora dos Laboratórios de Microscopia e Gemologia do Depto de Geologia, representa a UFC na Câmara Setorial da Mineração junto ao Governo do Estado do Ceará. Conselheira-Titular e Coordenadora da Câmara Especializada de Geologia e Minas/CREA-CE, Coordenadora da Comissão de Educação e Atribuição Profissional (CEAP 2023 e 2024) do CREA-CE.

Carlos William de Araújo Paschoal, Federal University of Ceará, Science Center, Department of Physics – Avenue Mister Hull, s/n – Pici University Campus, Block 928 – Fortaleza, CE – CEP 60.455-760, Brazil.

Possui graduação em Engenharia Elétrica pela Universidade Federal do Ceará (1995), mestrado em Física pela Universidade Federal do Ceará (1998) e doutorado em Física pela Universidade Federal do Ceará (2001). Atualmente é Professor Associado da Universidade Federal do Ceará. Tem experiência na área de Física, com ênfase em Prop. Óticas e Espectrosc. da Mat. Condens; Outras Inter. da Mat. com Rad. e Part., atuando principalmente nos seguintes temas: espectroscopia de impedância, infravermelho, transições de fase e espectroscopia Raman de materiais multiferróicos.

Tereza Falcão de Oliveira Neri, Federal University of Ceará, Science Center, Department of Geology – Avenue Mister Hull, s/n, Pici University Campus, Block 912 – Fortaleza, CE 60440-593 – CEP

Possui graduação em Geologia pela Universidade Federal do Ceará e mestrado em Agronomia (Solos e Nutrição de Plantas) pela Universidade Federal do Ceará. Doutorado em Geologia pela Universidade Federal do Ceará. Foi professora adjunto I da Universidade Federal do Ceará até 2017, atualmente é professora colaboradora. Tem experiência na área de Geociências, com ênfase em Mineralogia, atuando principalmente nos seguintes temas: mineralogia, minerais pesados, mapeamento, gênese de pegmatito, gemologia, petrologia e petrografia. Ao longo de 40 anos como docente recebeu prêmios e homenagens, incluindo os prêmios: Vanguarda Excelência em Ensino (2018) e Mulher na Geologia no Ceará (2021

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Publicado

2025-10-07

Como Citar

Gomes de Oliveira, I. (2025) “Gemology of Emeralds from Tauá, Brazil”, Anuário do Instituto de Geociências. Rio de Janeiro, BR, 48. doi: 10.11137/1982-3908_2025_48_67822.

Edição

v. 48 (2025): Anuário do Instituto de Geociências

Seção

Geologia

Licença

Creative Commons License
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