Micro‐Raman spectroscopic study of El Gasco pumice, western Spain

Abstract

A micro-Raman spectroscopic study of pumice materials from El Gasco (Sierra de Gata, Spain) has been performed for the first time. The obtained spectra allow the precise identification of the minerals, quartz, haematite, magnetite, ilmenite, rutile and anatase, in general agreement with results obtained by complementary techniques of X-Ray Diffraction (XRD) and Electron Microprobe. Also, fayalite and ferroan ringwoodite have been identified. The presence of high-pressure polymorphs indicates that the pumice rocks were subjected to high-pressure conditions quite similar to those observed in shock-induced molten and recrystallised materials, such as some meteorites and impact-related rocks.

Porcelain shards from Portuguese wrecks: Raman spectroscopic analysis of marine archaeological ceramics

“…The spectrum presented in Fig. 2f is most similar to that of ilmenite although the peak positions noted earlier are not an exact match with literature [27][28][29]. At temperatures above 960 °C it is known that ilmenite and hematite can form a solid solution (Ilm-Hem ss ), with the critical temperature at which the components are miscible in all proportions being ~650 °C [29].…”

Estudio espectroscópico y DRX de afloramientos terrestres volcánicos en la isla de Tenerife como posibles análogos de la geología marciana

“…Las identificaciones de las especies de óxidos/hidróxidos de Fe se han realizado en base a las vibraciones de los grupos activos en Raman para cada mineral. La hematite (α-Fe 2 O 3 ) posee las vibraciones principales a 220 295, 607 y el magnón a 1315 cm −1 (Rull et al, 2007); en cambio la magnetita (Fe 2+ (Fe 3+ ) 2 O 4 ) presenta sus vibraciones más intensas en la zona de 670 y 550 cm −1 (Jubb & Allen, 2010;Rull et al, 2007). Por último la goethita (α-FeO(OH)) presenta sus vibraciones a 248, 296, 386, 550 y 682 cm −1…”

Recent advances in linear and nonlinear Raman spectroscopy II

“…Temperature studies revealed the softening and broadening of most of these bands. The minerals quartz, hematite, magnetite, ilmenite, rutile and anatase were studied in pumice materials from El Gasco, Sierra de Gata, Spain, using micro-Raman spectroscopy and complementary X-ray diffraction and electron microprobe data by Rull et al 116 Several groups of minerals have been investigated by Frost et al 117 -129 These include samples of the humite mineral group [(A 2 SiO 4 n -A(OH,F) 2 where n represents the number of olivine and brucite layers in the structure and is 1, 2, 3 or 4 and A 2C is Mg, Mn, Fe or some mix of these cations], 117 the borosilicate mineral ferroaxinite, 118 uranopilite of different origins, 119 the uranyl oxyhydroxide hydrates: becquerelite, billietite, curite, schoepite and vandendriesscheite, 120 sampleite, lavendulan, zdenekite and the polymorph of lavendulan known as lemanskiite, 121 a series of joaquinite minerals, 122 …”