Microspatial analyses of the trace element composition of dental enamel are made possible using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Fine spatial resolution, multielement capabilities, and minimal sample destruction make this technique particularly well-suited for documenting the distribution of elements in sequentially calcifying layers of enamel. Because de...

1,2 , M. Humayun 1 , H. Downes 3 , S. Singletary 4 , J. A. Van Orman 5 and S. B. Jacobsen 2 1 National High Magnetic Field Laboratory and Department of Geological Sciences, [email protected]; 2 Department of Earth and Planetary Sciences, Harvard University; 3 School of Earth Sciences, Birkbeck University of London; 4 Department of Natural Sciences, Fayetteville State University; 5 Departm...

Introduction: Bulk ureilites have near chondritic abundances of siderophile elements [1-7], showing no correlation with Fe contents (~5-16 wt.%) or mg (molar Mg/[Mg+Fe]). These observations are difficult to reconcile with any igneous model for their silicates [8]. We address this problem through detailed characterization of the metal phases in ureilites [9], and petrologic modelling [10]. Here ...

Introduction: The concentrations of Ni, Ga, Ge, and Ir are typically used to assign an iron meteorite to one of the chemical groups [cf., 1-3]. The improvements in analytical techniques, mainly INAA, and the systematic study of a large number of iron meteorites resulted in the development of an extensive database on their chemical compositions [4] which has been used in deciphering the origins ...

We investigated the role that pulse width has on the analytical capabilities of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), specifically in the range of 40 fs to 300 ps. Three main results of LA-ICP-MS were examined: signal intensity or sensitivity, elemental fractionation or that the ablated aerosol is representative of the bulk, and detection limits of various ele...

In this collaborative investigation, femtosecond laser ablation-inductively coupled mass spectrometry (LA-ICP-MS) was applied to the study of a remarkable group of ancient Chinese gold objects in the Smithsonian’s Freer Gallery of Art and Arthur M. Sackler Gallery. Taking advantage of the superior ablation characteristics and high precision of a femtosecond 266 nm Ti:sapphire laser at Lawrence ...

A procedure was developed for the determination of element distributions in cross-sections of ferromanganese concretions using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The effects of carrier flow rates, rf forward power, ablation energy, ablation spot size, repetition rate and number of shots per point on analyte intensity were studied. It is shown that different...