Mineral Separation Laboratory
Efficient techniques for mineral separation are important in almost all geochronological studies. From year 2000, we have used the so called “water-based technique (pdf, new tab)” for separation of baddeleyite (and zircon). Baddeleyite is a reliable geochronometer for dating the crystallization of mafic and other silica-undersaturated rocks. The technique is based on the observation that small grains move much slower than large grains as they move across a Wilfley water-shaking table. In addition to the efficiency in extraction of very small (≤ 30 µm) baddeleyite grains, the water-based separation technique reduces the risk of cross-contamination, and is less costly (e.g., no heavy liquids are necessary) than conventional techniques. Over the years, baddeleyite from more than 70 samples of dykes and sills in Fennoscandia, Canada, South Africa and Zimbabwe have been successfully recovered in our lab. Typical yields for these rocks have been 200-300 grains/fragments per 0,5-1 kg sample.