Image analysis standard

The minerals industry is relying heavily on image analysis for the measurement of mineral properties to be able to optimize recovery of valuable minerals. Mineral quantification and measurement of mineral liberation are probably the most common tasks. At present there are no known standards to calibrate methods and procedures developed for this purpose. With the advent of standardization procedures, laboratories are compelled to be benchmarked and to use accepted standards. No generally accepted and certified methods are available for the measurement of mineral properties by image analysis.

The Industrial Mineralogy Interest Group of Minsa has embarked on a project to produce a standard for mineral quantification by scanning electron microscopy. The standard consists of a silicon chip with gold squares and circles of various exact sizes engraved on it. The standard would enable the mineralogist to:

• Measure the exact quantity of gold vs silicon with the associated errors
• Measure particle size with the associated errors
• Measure errors in the quantification of small particles
• Determine the effect of magnification on quantification of particles
• Determine the effect of orientation on quantification of particles
• Measure the ability of the software to separate and measure touching particles

The first standard has been produced and will be evaluated by various users and producers of image analysis equipment.

Johan de Villiers Jpdev@postino.up.ac.za