Procedures

The optical identification of minerals can be carried out by preparing a suitable sample and studying it through a petrographic microscope.

This work is made in my petrographic laboratory, where we prepare the thin sections of the samples for later study under a microscope.

This technique allows us to know if the studied rock is a meteorite or not, and to determine the compatibility with the known typologies, to be able to issue the corresponding report.

In accordance with official protocols, the identification of meteorites does not compromise that advanced techniques can vary sensibly or totally the appreciations obtained by petrography. The final official confirmation of the type of each meteorite must be given exclusively in the final classification process, where advanced nuclear techniques are used in the analyzes (geochemistry, isotopes, etc.). However, remember that even when a meteorite is classified with a specific type, it can undergo reclassification at any time, even when its typology has been made official at The Met. Bull.

By applying the polarized light microscopy technique, it is possible to identify rocks and minerals in thin section, the study of textures, structural alterations and many other data that will allow us to characterize meteorites.

According to the protocols, there will be occasions when it becomes necessary to carry out more specific, geochemical or isotope analyzes, in which case the client will be contacted to carry out the donation of the samples and the payment of the corresponding fees.  

It begins by preparing a polished sample and a thin sheet section for later optical and petrographic microscopic study by polarized light. If the sample is identified as a meteorite, its documentation and issuance of the analysis report are carried out.

In order to carry out this study, a sample of the rock is needed to make a polished surface and thin sections. The sample must not be smaller than 2 x 2 centimeters, as you can see in the corresponding section. A suitable surface is necessary to carry out the petrographic study. The Laboratory will NOT accept smaller samples, given the impossibility of working with them.

It is important that the sample has, if possible, a part of the outer zone and a part of the interior.

WHY A POLISHED SECTION AND A THIN SECTION?

The first test to which the sample is subjected is carried out with a geological optical microscope, incident light, and on a polished surface. In most cases it is enough to know whether or not the rock is a meteorite. If it were meteorite, or if there was still any doubt about its nature, we proceed to the study of a thin section in the microscope after equipping it with the corresponding polarizing filters, with which to know the mineral composition and document textures and components in order to its identification.

We enclose in this page a scheme of the procedure that will be carried out, approved in protocol 01/2016 of the IDENMET program (Meteorite Identification and Classification).

The final step towards the official classification is not mandatory, although it is recommended, and such a procedure is another independent of this, involving the donation of new samples and the payment of fees that have been imposed by the Universities where we will carry out the process.  With the Official classification, the meteorite will obtain the official authenticity certification.

WARNING!

This laboratory does NOT work with photographs or issue conclusions or opinions without prior scientific study of a physical sample of the rock.

In the analyzes that we will carry out, it will be determined whether or not the samples are meteorites, and in this case of what type. It is not the responsibility of this laboratory or our study protocol to know what types of terrestrial rocks they are.

The identification of meteorites does not compromise that advanced techniques can vary sensibly or totally the appreciations obtained by petrography. The final official confirmation of the type of each meteorite must be given exclusively in the final classification process, where advanced nuclear techniques are used in the analyzes (geochemistry, isotopes, etc.). However, remember that even when a meteorite is classified with a specific type, it can undergo reclassification at any time, even when its typology has been made official at The Met. Bull.