Granite may have more alkali feldspar, whereas a granite derived from partial melting of metaigneous rocks may be richer in plagioclase. It is on this basis that the modern "alphabet" classification schemes are based. The letter-based Chappell & White classification system was proposed initially to divide granites into I-type (igneous source) granite and S-type (sedimentary sources). Both types are produced by partial melting of crustal rocks, either metaigneous rocks or metasedimentary rocks. M-type granite was later proposed to cover those granites that were clearly sourced from crystallized mafic magmas, generally sourced from the mantle. However, this proposal has been rejected by
This Is What Rock n' Roll Looks Like been used by Lady Gaga. Ian Drew of "Us Weekly" called the single "shocking" and "electric". Allison Stewart of "The Washington Post" gave "This Is What Rock ‘n’ Roll Looks Like” a mixed review, describing Porcelain Black as a "girl-fronted version of Mötley Crüe circa Dr. Feelgood". Jon Wiederhorn of "Inked" dubbed the song "a euphoric digital feast of raspy melodic vocals, four-to-the-floor beats, and keyboards that buzz like electric guitars." "This Is What Rock n' Roll Looks Like" debuted on the U.S. "Billboard" Hot Dance Club Songs at number forty-six, on the week ending July 18, 2011. The following