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 to be proud of who they are. Vocally, Porcelain Black sings as if straining through "a maze of razorblades," according to Steven J. Horowitz of "YRB Magazine". The RedOne-produced track employs a beat that is reminiscent of his work with Lady Gaga. Porcelain Black screams in the chorus "Hey hey hey if you're ready to rage / Raise your hands up, this what rock and roll looks like / Yeah yeah yeah, wearing leather and lace / Raise your hands up, this what rock and roll looks like." While being interviewed by the "Los Angeles Times", Porcelain Black discussed in