Inclusions

Overview & Synopsis

This book is a compilation of the best images collected for the ECROFI 2017 meeting, held in Nancy (France) in June 2017. Our immense thanks go to the ECROFI participants from across the world who sent us images to include in the book. The objective of this publication is to share photomicrographs with people from both inside and outside the "inclusionist" community. Geologists and those from the inside will discover how inclusions can help them to reconstruct the distant past over timescales of thousands to billions of years. Non-specialists, our readers from the outside, will be surprised by the diversity and beauty of the world of these microscopic inclusions.Inclusions are micro-cavities found within crystals of any nature -mineral, organic, natural or synthetic. These small defects in the crystal lattice are filled by liquid, gas, minerals or magmatic glasses. Inclusions can vary in size from only a few micrometers for the smallest (1 µm = 1/1000 mm) to up to a few millimeters for the biggest. In most cases, a microscope is needed to observe the inclusions under natural white light or UV illumination. Other recent techniques are used to determine the nature of the phases in the inclusions. The temperatures of phase transitions (solid into liquid, liquid into gas) can be measured using special thermal stages adapted to the microscope. These data allow the scientist to reconstruct the temperature and pressure of the inclusions at the time of their formation and, by consequence, the conditions that prevailed during the formation of mountains, rifts and volcanoes, ore deposits, oil and gas fields, gems and meteorites. Synthetic minerals are also inclusion-rich and, from these, the scientific community can learn a lot about the conditions of synthesis, helping them to improve the efficiency of the production processes. As you turn from page to page, we hope you enjoy exploring the world of inclusions and discovering their amazing shapes and forms as well as their extraordinary compositional complexity.