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Experimental determination of the pressure and temperature controls on Ti solubility in quartz provides a calibration of the Ti-in-quartz (TitaniQ) geothermometer applicable to geological conditions up to ~ 20 kbar. We present a new method for determining 48Ti mass fractions in quartz by LA-ICP-MS at the 1 μg g−1 level, relevant to quartz in HP-LT terranes. We suggest that natural quartz such as the low-CL rims of the Bishop Tuff quartz (determined by EPMA; 41 ± 2 μg g−1 Ti, 2s) is more suitable than NIST reference glasses as a reference material for low Ti mass fractions because matrix effects are limited, Ca isobaric interferences are avoided, and polyatomic interferences at mass 48 are insignificant, thus allowing for the use of 48Ti as a normalising mass. Average titanium mass fraction from thirty-three analyses of low temperature quartz from the Czech Erzgebirge is 0.9 ± 0.2 μg g−1 (2s) using 48Ti as a normalising mass and Bishop Tuff quartz rims as a reference material. The 2s average analytical uncertainty for individual analyses of 48Ti is 8% for 50 μm spots and 7% for 100 μm spots, which offers much greater accuracy than the 21–41% uncertainty (2s) incurred from using 49Ti as an analyte.

Halogen contents for the widely distributed reference glasses BHVO-2G, BIR-1G, BCR-2G, GSD-1G, GSE-1G, NIST SRM 610 and NIST SRM 612 were investigated by pyrohydrolysis combined with ion chromatography, total reflection X-ray fluorescence analysis, instrumental neutron activation analysis, the noble gas method, electron probe microanalysis and laser ablation-inductively coupled plasma-mass spectrometry. Glasses BHVO-2G, GSD-1G and GSE-1G have halogen contents that can be reproduced at the 15% level by all bulk techniques and cover a significant range in halogen mass fractions for F (~ 20–300 μg g), Cl (~ 70–1220 μg g) and Br (~ 0.2–285 μg g) and I (~ 9–3560 ng g). The BIR-1G glass has low F (< 15 μg g), Cl (~ 20 μg g), Br (15 ng g) and I (3 ng g). The halogen contents for the silica-rich NIST SRM 610 and 612 glasses were poorly reproduced by the different techniques. The relatively high Cl, Br and I abundances in glasses GSD-1G and GSE-1G mean that these glasses are well suited for calibrating spatially resolved micro-analytical studies on silicate glasses, melt and fluid inclusions. Combined EPMA and laser ablation-inductively coupled plasma-mass spectrometry data for glass GSE-1G demonstrate homogeneity at the 10% level for Cl and Br.

We report homogeneity tests on large natural apatite crystals to evaluate their potential as U reference materials for apatite fission-track (AFT) thermochronology by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The homogeneity tests include the measurements of major element concentrations by electron probe microanalysis (EPMA), whereas for U concentration, isotope dilution (ID) ICP-MS and laser ablation (LA) ICP-MS were employed. Two apatite crystals are potential reference materials for LA-ICP-MS analysis: a 1 cm3 fraction of a Durango crystal (7.5 μg g−1 U) and a 1 cm3 Mud Tank crystal (6.9 μg g−1 U). The relative standard deviation (1 RSD) of the U concentration determined by ID-ICP-MS of both apatite crystals was ≤ 1.5%, whereas 1 RSD for the LA-ICP-MS results was better than 4%, providing sufficient homogeneity for fission-track dating. The results on the U homogeneity for two different apatite samples are an important step towards establishing in situ dating routines for AFT analysis by LA-ICP-MS. Nous restituons des tests d'homogeneite sur des grands cristaux d'apatite naturelle afin d’evaluer leur potentiel en tant que materiaux de reference pour l'U en vue d'une application dans le domaine de la thermochronologie par traces de fission sur apatite (AFT) par spectrometrie de masse a plasma induit couplee a l'ablation laser (LA-ICP-MS). Les tests d'homogeneite incluent des mesures des concentrations en elements majeurs par microsonde electronique (EPMA), alors que pour la concentration en U, la dilution isotopique (ID) ainsi que l'ablation laser (LA) ICP-MS ont ete employees. Deux cristaux d'apatite sont des materiaux de reference possibles pour les analyses LA-ICP-MS: une fraction d'1 cm3 d'un cristal de Durango (7,5 µg g−1 U) et un cristal d'1 cm3 de Mud Tank (6,9 µg g−1 U). L’ecart type relatif (1 RSD) de la concentration en U determinee par ID-ICP-MS des deux cristaux d'apatite est ≤ 1,5%, tandis que celui pour les resultats LA-ICP-MS est inferieur a 4%, offrant ainsi une homogeneite suffisante pour les datations par la methode des traces de fission sur apatite. Les resultats concernant l'homogeneite de l'U pour deux echantillons differents d'apatite sont une etape importante vers la possibilite d'envisager des datations AFT in situ en routine par LA-ICP-MS.

Two large pegmatitic crystals of sodic pyroxene (aegirine) and sodic amphibole (arfvedsonite) from the agpaitic igneous Ilimaussaq Complex, south Greenland were found to be suitable as reference materials for in situ Li isotope determinations. Lithium concentrations determined by SIMS and micro-drilled material analysed by MC-ICP-MS generally agreed within analytical uncertainty. The arfvedsonite crystal was homogeneous with [Li] = 639 ± 51 μg g−1 (2s, n = 69, MC-ICP-MS and SIMS results). The aegirine crystal shows strongly developed sector zoning, which is a common feature of aegirines. Using qualitative element mapping techniques (EPMA), the homogeneous core of the crystal was easily distinguished from the outermost sectors of the crystals. The core had a mean [Li] of 47.6 ± 3.6 μg g−1 (2s, n = 33) as determined by SIMS. The seven micro-drilled regions measured by solution MC-ICP-MS returned slightly lower concentrations (41–46 μg g−1), but still overlap with the SIMS data within uncertainty. Based on MC-ICP-MS and SIMS analyses, the variation in δ7Li was about 1‰ in each of the two crystals, which is smaller than that in widely used glass reference materials, making these two samples suitable to serve as reference materials. There was, however, a significant offset between the results of MC-ICP-MS and SIMS. The latter deviated from the MC-ICP-MS results by −6.0 ± 1.9‰ (2s) for the amphibole and by −3.9 ± 1.9‰ (2s) for the aegirine. This indicates the presence of a significant matrix effect in SIMS determinations of Li isotopes for amphibole and pyroxene relative to the basalt glasses used for calibration. Based on the MC-ICP-MS results, mean δ7Li values of +0.7 ± 1.2‰ (2s, n = 10) for the arfvedsonite crystal and of −3.7 ± 1.2‰ (2s, n = 7) for the core of the aegirine crystal were calculated. Adopting these values, SIMS users can correct for the specific IMF (instrumental mass fractionation) of the ion probe used. We propose that these two crystals serve as reference materials for in situ Li isotope determinations by SIMS and pieces of these two crystals are available from the first author upon request. Deux grands cristaux pegmatitiques, un pyroxene sodique (aegerine) et une amphibole sodique (arfvedsonite) provenant du complexe agpaitique Ilimaussaq (sud du Groenland) ont ete selectionnes pour etre des materiaux de reference lors d'analyses in situ des isotopes de Li. Les concentrations en lithium ont ete determinees par SIMS et par MC-ICP-MS sur du materiel preleve par micro-forage. Les deux determinations sont en accord aux erreurs analytiques pres. Le cristal de arfvedsonite est homogene avec [Li] = 639 ± 51 μg g−1 (2s, n = 69, donnees MC-ICP-MS et SIMS). Le cristal d'aegerine presente des zonations tres franches, comme il est classique dans les aegerines. En utilisant les techniques de cartographie chimique qualitative des elements (EMPA) il a ete possible de clairement distinguer le cœur du cristal, homogene, de ses bordures zonees. Le cœur a un [Li] moyen de 47.6 ± 3.6 μg g−1 (2s, n = 33) d'apres l'analyse par SIMS. Les sept regions micro forees et analysees par MC-ICP-MS en solution presentent des concentrations legerement inferieures (41–46 μg g−1) mais qui neanmoins sont dans la meme gamme, aux erreurs analytiques pres, que celles determinees par SIMS. Les donnees obtenues par MC-ICP-MS et SIMS montrent que la variation de δ7Li dans chaque cristal est de 1‰, ce qui est bien inferieur a celle mesuree dans les verres de reference generalement utilises. Ces deux echantillons sont donc tres adaptes a une utilisation comme materiaux de reference. Il y a neanmoins un decalage significatif entre les donnees de MC-ICP-MS et les donnees obtenues par SIMS, ces dernieres different des premieres de −6.0 ± 1.9‰ (2s) pour l'amphibole et de −3.9 ± 1.9‰ (2s) pour l'aegerine. Ceci demontre l'existence d'un effet de matrice non negligeable lors de l'analyse par SIMS des isotopes de Li dans des amphiboles et des pyroxenes, par rapport au verre basaltique utilise pour la calibration. Les valeurs moyennes de δ7Li de +0.7 ± 1.2‰ (2s, n = 10) pour le cristal d'arfvedsonite et de −3.7 ± 1.2‰ (2s, n = 7) pour le cœur du cristal d'aegerine ont ete calculees a partir des donnees obtenues par MC-ICP-MS. Les utilisateurs de SIMS peuvent utiliser ces valeurs pour corriger leurs resultats du fractionnement de masse instrumental (IMF) specifique a la sonde ionique utilisee. Nous proposons d'utiliser ces deux cristaux comme materiaux de reference lors de determinations in situ des isotopes de Li par SIMS et des fragments de ces deux cristaux peuvent etre demandes au premier auteur.

Eleven synthetic silicate and phosphate glasses were prepared to serve as reference materials for in situ microanalysis of clinopyroxenes, apatite and titanite, and other phosphate and titanite phases. Analytical results using different micro-analytical techniques showed that the glass fragments were homogeneous in major and trace elements down to the micrometre scale. Trace element determinations using inductively coupled plasma-mass spectrometry (ICP-MS), multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) and secondary ionisation mass spectrometry (SIMS) showed good agreement for most elements (Li, Be, B, Cs, Rb, Ba, Sr, Ga, Pb, U, Th, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Tm, Yb, Lu, Zr, Hf, Ta, Nb) studied and provide provisional recommended values. Onze verres synthetiques de compositions silicatee et phosphatee ont ete prepares afin de servir de materiaux de reference pour la micro-analyse in situ de clinopyroxenes, d'apatites et de titanites et d'autres phases phosphatees et titaniferes. Les resultats analytiques obtenus a partir de differentes techniques de micro-analyse ont montre que les fragments de verre etaient homogenes en elements majeurs et en trace, ceci jusqu'a l'echelle du micrometre. Les determinations des concentrations en elements en trace, faites par spectrometrie de masse a plasma inductif (ICP-MS), spectrometrie de masse a plasma inductif et multi-collecteur (MC-ICP-MS), spectrometrie de masse a plasma inductif et ablation laser (LA-ICP-MS) et spectrometrie de masse a ionisation secondaire (SIMS) ont montre un bon accord entre elles, pour la plupart des elements etudies (Li, Be, B, Cs, Rb, Ba, Sr, Ga, Pb, U, Th, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Tm, Yb, Lu, Zr, Hf, Ta, Nb) et permettent de proposer des valeurs recommandees provisoires.

The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories - virtually all those performing geochemical boron isotope analyses in the world -which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution. L'Istituto di Geoscienze e Georisorse (IGG), pour le compte et avec le soutien de l'Agence Internationale de l'Energie Atomique (AIEA), a prepare huit materiaux geologiques (trois eaux naturelles et cinq roches et mineraux) destines a la conduite d'une comparaison en aveugle des mesures de composition isotopique et de concentration du bore entre differents laboratoires. Vingt-sept laboratoires -pratiquement tous ceux qui travaillent sur les isotopes du bore en geochimie - ont accepte de participer a cette intercomparaison, mais quinze seulement ont finalement envoye leurs donnees de composition isotopique et/ou de concentration du bore. Les resultats demontrent que la precision des valeurs indiquee par les laboratoires reflete mal la reproductibilite entre laboratoires des mesures de composition isotopique comme de concentration du bore. Les raisons de ces discordances peuvent comprendre l'existence de fractionnements isotopiques dus aux matrices chimiques des materiaux, un deplacement relatif du zero de l'echelle de δ11B, ainsi que le manque de materiaux bien caracterises pour calibrer les mesures de concentration du bore. Les materiaux utilises pour l'intercomparaison des mesures sont maintenant a disposition a l'AIEA (materiaux solides) et l'IGG (eaux) pour etre distribues.