Petrography rock was affixed to a microscope slide and then ground so thin that light could be transmitted through mineral grains that otherwise appeared opaque. The position of adjoining grains was not disturbed, thus permitting analysis of rock texture. Thin section petrography became the standard method of rock study. Since textural details contribute greatly to knowledge of the sequence of crystallization of the various mineral constituents in a rock, petrography progressed into petrogenesis and ultimately into petrology. It was in Europe, principally in Germany, that petrography advanced in the last half of the nineteenth century. The macroscopic characters of rocks, those
What Love Is Made Of performed "What Love Is Made Of". She also performed it during her headline set at the Yahoo! Wireless Festival 2013. What Love Is Made Of "What Love Is Made Of" is a song recorded by British recording artist Katy B. Written by Katy alongside Goldon Warren, who also produced it under the name Geeneus, the track was released as a standalone single via digital retailers on 8 July 2013 by Rinse and Columbia Records. It was composed after Katy had been listening to dance genres. The theme conveyed in the lyrics is love while musically, the song has been described