Which of the following statement is true in concentration of ore?
Gravity separation also called levigation and particularly suitable for heavy oxides and Carbonate ores.
Levigation is used to concentrate the ore. In other words, we want to enhance the percentage of the metal (or element) in the ore. This process takes advantage of the difference in the specific gravities of ore and gangue particles. Thus it is suitable for heavy oxide ores or Carbonate ores (where difference in specific gravity in large).
Froth floatation, is a suitable method to concentrate sulphide ores. It is not based on 'solubility'. Rather, it is based on the principle of differential wettability of the ore and gangue particles.
Electromagnetic separation works when either ore or gangue are magnetic (attracted to magnets) in nature.
Crushing and grinding happen before concentration. It is not a concentration process at all.