Heavy Minerals

Detrital heavy mineral analysis is one of the most rewarding techniques for sedimentary provenance studies. There are a large variety of heavy mineral species present in detrital rocks, and many of them primarily crystallise only in specific rock types. For example, Cr spinel is diagnostic of peridotitic detritus, whereas kyanite and staurolite indicate contribution from high grade metamorphic sources. Typological studies (shape, colour, roundness, surface frosting and, when visible, zoning) of dominant heavy mineral species add further details to provenance interpretation. A key advantage of typological studies is that they describe variations within the individual heavy mineral species that behave similarly during secondary sedimentary processes (e.g. weathering, hydraulic sorting and diagenetic dissolution) and are therefore unaffected by them.

At Origin Analytical we characterise abundances and morphologies of up to 200 non-opaque and non-micaceous heavy minerals. Heavy minerals are separated using a non-toxic LST Fastfloat heavy liquid (2.80 g/cm3) and funnels separation technique. Identification is performed using optical microscopy and point counting is carried out with Petrog digital stepping stage. We also offer brief provenance interpretation, summarised in a report illustrated with microphotographs or common heavy minerals and their morphological types.