METHOD AND APPARATUS FOR THE CLASSIFICATION OF MATTER

摘要

One aspect of the invention concerns a method of classifying particles according to their composition. In the method the particles (12, 68, 200) are irradiated with electromagnetic radiation, typically X-radiation, at respective first and second energy levels. First and second values are derived which are representative of the attenuation of the radiation by each particle. A third value is then derived as the difference between or ratio of the first and second values, and the particles are classified according to whether the third value is indicative of the presence in the particles of a particular substance. In one application of the method it can be used to classify diamondiferous kimberlite into a fraction consisting of kimberlite particles containing diamond inclusions and a fraction consisting of barren kimberlite particles.