Mubice bya minerval bigize granite, hejuru ya 90% harimo feldspar na quartz, muribyo feldspar niyo myinshi.Feldspar ikunze kuba umweru, imvi, ninyama-umutuku, kandi quartz ahanini iba idafite ibara cyangwa ibara ryera ryera, bigize ibara ryibanze rya granite.Feldspar na quartz ni minerval ikomeye, kandi biragoye kugenda ukoresheje icyuma.Naho ibibara byijimye muri granite, cyane cyane mika yumukara, hari andi mabuye y'agaciro.Nubwo biotite yoroshye, ubushobozi bwayo bwo kurwanya imihangayiko ntabwo ari intege nke, kandi mugihe kimwe bafite granite nkeya, akenshi ntibiri munsi ya 10%.Nibintu bifatika granite ikomeye cyane.
Indi mpamvu ituma granite ikomeye ni uko imyunyu ngugu yayo ihambiriye cyane kandi igashyirwa hamwe.Imyenge ikunze kuba munsi ya 1% yubunini bwurutare.Ibi biha granite ubushobozi bwo guhangana ningutu zikomeye kandi ntabwo byoroshye kwinjira mubushuhe.
Igihe cyo kohereza: Gicurasi-08-2021