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
Rock art of Uganda thought. Archaeologists strive to better understand cultures of the past, figuring out the meanings behind these paintings could help archaeologists to better understand what culture made them. Nyero is one of the most important rock art sites not just in Uganda but in Africa as well. It has well-preserved rock paintings that are utilized in study of rock art. The Nyero site was discovered by C.A.E Harwich in 1945. Nyero was the first rock art site to be catalogued and described in full within Uganda. Nyero itself is composed of granite, and just under 40m high. There are two areas