Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Olivine (Mg,Fe)2SiO4 11 Grey / brown 5 YR 3 1 Very dark Abundant Mostly Very Sub Quartz SiO2 grey 0.1 mm or poor angular Calcite CaCO3 less, few and sub Plagioclase NaAlSi3O8 – larger rounded CaAl2Si2O8 ones 12 Black / grey 10 YR 2 1 Black Moderate 0.2 0.5 Poor Very Quartz SiO2 – with lighter (main) mm angular Plagioclase NaAlSi3O8 – brown edges CaAl2Si2O8 Sanidine (K,Na)AlSi3O8
Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Olivine (Mg,Fe)2SiO4 11 Grey / brown 5 YR 3 1 Very dark grey Abundant Mostly 0.1 mm or less, few larger ones Very poor Sub angular and sub rounded Quartz SiO2 Calcite CaCO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8 12 Black / grey with lighter brown edges 10 YR (main) 2 1 Black Moderate 0.2 – 0.5 mm Poor Very angular Quartz SiO2 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8