The present invention relates to a froth flotation mechanism located in a flotation cell, comprising a directional element suspended from the lower end of a hollow shaft extending to the lower section of the cell and vertical vanes attached to said directional element, which extend above and below the directional element and horizontally beyond the directional element. The disk drive further comprises a plurality of code segments including a read channel interface procedure having an input parameter comprising a pointer to a data structure. The compensating element includes first and second switch contact carriers provided with switch contacts that correspond to the fixed contacts. The optical ceramic may have a high refractive index and a low dispersion.