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
Granite, Colorado inches is provided for it is not considered that the prescribed limit can with reasonable safety be exceeded. While Granite is a ghost of what it once was, what with both a railroad and a major highway running through it has survived the years. However, many old ghost towns remain in the hills surrounding Granite. As the prospectors searched for gold, every Arkansas River tributary was a potential gold mining site and a chance to strike it rich. About two miles south of Granite, Clear Creek empties into the Arkansas River. Although prospecting took place in this area as early