Results 41 to 50 of about 9,686 (212)

Some notes on the IUGS classification of lamprophyric rocks

Mineralogia
The lamprophyric rocks are uncommon volatile-rich melanocratic porphyritic rocks which contain only mafic phenocrysts. The felsic minerals are confined in the groundmass. They occur as dikes, sills and diatremes.
Kamvisis Ioannis, Phani Pothuri Ramesh Chandra   +1 more
doaj   +1 more source

Composição Química da Turmalina de Turmalinitos Estratiformes da Mina de Passagem de Mariana, Sudeste do Quadrilátero Ferrífero (MG)

Geologia USP. Série Científica, 2009
A mina subterrânea de Passagem de Mariana é uma das minas de ouro mais antigas do Brasil. O ouro associa-se a turmalinitos estratiformes e veios e brechas de quartzo e carbonato com turmalina.
Gianna Maria Garda, Johann Hans Daniel Schorscher, Paulo Beljavskis, Marcos de Souza Mansueto, Margareth Sugano Navarro, Andrezza Alves Mota   +5 more
doaj   +1 more source

Gipsgärten: Selbstorganisierte röhrenförmige Strukturen aus Calciumsulfat mit Relevanz für die Suche nach außerirdischem Leben

Angewandte Chemie, Volume 137, Issue 48, November 24, 2025.
Chemische Gärten sind selbstorganisierte abiotische Strukturen mit „lebensähnlichen” Formen. Hier zeigen wir, dass solche Prozesse auch nach Zugabe konzentrierter Sulfatlösungen zu festen Calciumsalzen ablaufen und sogenannte Gipsgärten ergeben. Die dafür nötigen Bedingungen sind weitgehend kompatibel mit den geochemischen Verhältnissen auf dem frühen ...
Selina Reigl, Elisabeth Wagner, Carlos Pimentel, Werner Kunz, Alexander E. S. Van Driessche, Matthias Kellermeier   +5 more
wiley   +1 more source

Integrating rotational components to optical properties observed in petrographic thin sections via automated image acquisition and analysis

Mineralogia
The analysis of petrographic thin sections is a widely used process for the identification of the mineralogy of rocks and the analysis of their textural and microstructural characteristics.
Pretorius Jacob Johannes, Mayne Matthew Jason   +1 more
doaj   +1 more source

Britholite-(Ce) from the metaluminous granite of SW Egypt

Mineralogia, 2023
Optical microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analyses were used to characterize britholite-(Ce) of the metaluminous granite (Proterozoic) intruded into the Nubian Formation in southwestern Egypt and ...
Hassan Kamaleldin M.
doaj   +1 more source

Gypsum Gardens: Self‐Assembled Tubular Structures of Calcium Sulfate with Relevance for the Detection of Extraterrestrial Life

Angewandte Chemie International Edition, Volume 64, Issue 48, November 24, 2025.
Chemical gardens are self‐assembled architectures with “life‐like” morphologies that form in the absence of any biological activity. Here we show that such structures can also be obtained by contacting reservoirs of calcium and sulfate ions, under conditions that plausibly emulate those prevailing on early Mars.
Selina Reigl, Elisabeth Wagner, Carlos Pimentel, Werner Kunz, Alexander E. S. Van Driessche, Matthias Kellermeier   +5 more
wiley   +1 more source

A phlogopite-amphibole-plagioclase bearing websterite from Guinadji volcano (Adamawa Plateau, Northern Cameroon): evidence of a cumulate origin and crustal event

Mineralogia
An unusual phlogopite-amphibole-plagioclase-bearing websterite xenolith has been sampled in an alkali basaltic pyrolastite from Guinadji volcano, SE Ngaoundéré, Adamawa plateau, northern Cameroon, eastern extension of the continental sector of the ...
Kagarabi Paterne Mulimbi, Ntaflos Theodoros, Tamen Jules, Nkouathio David G., Tumba Kaniki   +4 more
doaj   +1 more source

Alteração mineralógica de Neossolos em uma climo-litossequência no Planalto do Rio Grande do Sul Mineral weathering in Neossolos in a climo-litosequence on the Rio Grande do Sul Plateau, Brazil

Ciência Rural, 2012
No Estado do Rio Grande do Sul (RS), os Neossolos Litólicos e Neossolos Regolíticos são solos que têm sofrido forte pressão de uso, demandando maior conhecimento sobre sua gênese e mineralogia.
Fabrício de Araújo Pedron, Antonio Carlos de Azevedo, Ricardo Simão Diniz Dalmolin   +2 more
doaj   +1 more source

Modulation of the Acidity of HY, HBETA, and HZSM‐5 Zeolites by Lanthanum Incorporation for Selective Gasoline Desulfurization in the FCC Riser

ChemCatChem, Volume 17, Issue 21, November 10, 2025.
Desulfurization in the FCC riser is achieved by modifying zeolite catalysts with La3+ ions, promoting H2S formation from thiophenic compounds while suppressing secondary reactions. This approach enhances gasoline quality by increasing selectivity for H2S and enabling efficient condensation and alkylation, supporting cleaner fuel production and ...
Ronaldo C. Santos, Daniel F. Almeida, Anderson C. dos S. Silva, Yiu L Lam, José M. M. Ferreira, D. Ballesteros‐Plata, Enrique Rodríguez‐Castellón, Agustin Martínez, Luiz A. M. Pontes   +8 more
wiley   +1 more source

8. Reunion de la Sociedad EspaNola de Mineralogia

, 1988
Available from Centro de Informacion y Documentacion Cientifica CINDOC. Joaquin Costa, 22. 28002 Madrid.
Sociedad EspaNola de Mineralogia, Madrid (Spain)
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