Metal and Mining

In this study we have chosen to investigate pyrite and its surrounding minerals in order to identify the different mineral phases as well as the chemical variations from micro- to nano-scale. Using the different microscopes instruments and being co-localized allows a comprehensive characterization of the sample and a precise superimposition of all the images.

Gemstones for jewelry are treated by heating, irradiation, or filling of cracks to make them flawless. We performed imaging analyses using an XGT-9000 X-ray Analytical Microscope on a ruby provided by Mineralab. The transmission X-ray imaging revealed that the ruby included several internal defects, and the fluorescent X-ray imaging revealed that the ruby surface was treated by filling with Pb, Mg and Si which are representative of lead glass.

The XGT-9000 Series can be equipped with various probes and spot sizes providing comprehensive and detailed understanding of geological and mineral samples.

In this article, we present how our Raman and X-Ray Fluorescence microscopies can be combined to shed some light on the origins of the universe. We show some examples on a meteorite piece and on water inclusion in quartz matrix.

Lapis lazuli is a deep-blue metamorphic rock used as a semiprecious stone which contains inclusions that can impact its value. Pyrite impurities and major elements distribution are studied with the XGT-9000, HORIBA’s new X-ray microscope.

Natural rocks composing the Earth are complex. They consist of an aggregate of one or more minerals. Each mineral can be defined by its chemical composition and its crystalline structure and sometimes can also contain fluid inclusions. Geologists need a powerful characterization technique to get detailed information on the rock formation history. Raman spectroscopy is extremely information-rich (chemical identification, characterization of molecular structures, effects of bonding, environment and stress on a sample). With its non-destructive properties and high spatial resolution (< 1 μm), it is thus a tool of choice for geological studies.

Many particles encountered in mining are characterized by sieves. Recent advances make image analysis practical for samples with sizes larger than several microns in diameter. As particle size decreases, laser diffraction becomes the technique of choice.

Hydraulic fracturing is used in the oil and gas industry to increase the flow of oil and/or gas from a well. Proppants are pumped into the oil well with fracturing fluid to hold the fissures open. The proppant size, shape, and mechanical strength influences the integrity of the newly created fractures, and therefore the flow of oil and gas out of the well.

In this work, spectroscopic ellipsometry (SE) was successfully applied to characterize the optical properties and the thicknesses of doped and undoped diamond layers. The sensitivity of this technique enables the doped layer to be distinguished from the undoped one in a sample consisting of a stack of these two layers. Moreover, an interface between the two layers has been detected. This work and others reported previously show clearly that ellipsometry is the technique of choice for the characterization of optical and structural properties of layered materials thanks to its sensitivity and the wide range of information it provides.

In this work, spectroscopic ellipsometry (SE) was successfully applied to characterize the optical properties and the thicknesses of doped and undoped diamond layers. The sensitivity of this technique enables the doped layer to be distinguished from the undoped one in a sample consisting of a stack of these two layers. Moreover, an interface between the two layers has been detected. This work and others reported previously show clearly that ellipsometry is the technique of choice for the characterization of optical and structural properties of layered materials thanks to its sensitivity and the wide range of information it provides.