Supplementary Material Table S: Mineral Content of Samples as Determined by Optical Microscopy on Thin Sections Sample number Appearance of thin section Munsell Colour Inclusion characteristics Inclusion identities Hue Value Chroma Colour Size range Sorting Roundness / Shape Name Chemical composition 1b Orangey red with black core 5 YR (main) 2.5 4 6 red Black Abundant Mostly 0.1 – 0.5 mm, some bigger 1.0 – 1.5 mm Very Poor Very angular and sub rounded Quartz SiO2 Calcite CaCO3 Olivine (Mg,Fe)2SiO4 (Mg,Fe)SiO3 Plagioclase NaAlSi3O8 –
YR (core) 2.5 1 CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Microcline KAlSi3O8 2 Reddish black 5 YR 2.5 1 Black Abundant 0.05 – 1.0 mm, most around 0.2mm Very poor Angular Quartz SiO2 Calcite CaCO3 Kaersutite Sanidine (K,Na)AlSi3O8 (Mg,Fe)SiO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8
3 Yellowy red 5 YR 4 6 red Moderate Mostly 0.1 – 0.2 mm, few larger around 0.5mm Poor Mostly sub rounded, few larger angular ones Quartz SiO2 Calcite CaCO3 Olivine (Mg,Fe)2SiO4 Monticellite Ca(Mg,Fe)2SiO4 Sanidine (K,Na)AlSi3O8 Unknown black mineral 4a Orangey Red 5 YR 5 6 red Abundant 0.2 – 0.5 mm Poor Angular and sub rounded Quartz SiO2 Calcite CaCO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8
Olivine (Mg,Fe)2SiO4 Kaersutite 4b Yellowish brown 10 YR 5 6 brown Sparse 0.3 – 1.0 mm – mostly around 0.5 mm Very Poor Very Angular Quartz SiO2 Calcite CaCO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Olivine (Mg,Fe)2SiO4 Monticellite Ca(Mg,Fe)2SiO4 Kaersutite
5a Very red 10 R 4 6 Red Moderate 0.1 – 0.3 mm Very poor Angular Quartz SiO2 Sanidine (K,Na)AlSi3O8 Olivine (Mg,Fe)2SiO4 (Mg,Fe)SiO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Monticellite Ca(Mg,Fe)2SiO4 6b Red with thin black core 5 YR (main) 5 6 red Abundant 0.5 – 1.5 mm Very poor Very angular Unknown black / red mineral
YR brown abundant mm angular Quartz SiO2 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Olivine (Mg,Fe)2SiO4 Monticellite Ca(Mg,Fe)2SiO4 7a Red 2.5 YR 4 6 Red Very abundant Most 0.05 – 0.1 mm, rest 0.3 – 0.5 mm Fair Sub rounded with few larger very angular Quartz SiO2 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Unknown
black / red mineral 7b Red 2.5 YR 4 6 Red Abundant Large range 0.2 -1.0 mm Poor Angular Quartz SiO2 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Olivine (Mg,Fe)2SiO4 Monticellite Ca(Mg,Fe)2SiO4 9 Pale red 5 YR 5 6 red Abundant Mostly 0.1 -0.2 mm with fewer larger 1.0 -1.5 mm Poor Sub angular and rounded Quartz SiO2 Calcite CaCO3 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8
Unknown black / red mineral 10b Black with red edges 5 YR (main) 2.5 YR (edge) 3 4 3 8 Dark reddish brown Red Very abundant Large range – all sizes from 0.05 – 1.0 mm Very poor Very angular Quartz SiO2 Calcite CaCO3 Olivine (Mg,Fe)2SiO4 Plagioclase NaAlSi3O8 – CaAl2Si2O8 10c Red 5 YR 4 4 Reddish brown Very abundant 0.1 - 0.2 mm Fair Angular Quartz SiO2 Calcite CaCO3
5 YR 3 3 Dark reddish brown (Mg,Fe)SiO3 Kaersutite 13 Red with thin black core 10 R (main) 2.5 YR (core) 3 2.5 6 1 Dark red Reddish black Moderate Mixture of 0.1 – 0.2 mm and 0.5 – 1.0 mm Poor Mixture of very angular and very rounded Quartz SiO2 Unknown black / red mineral 14 Orange / brown 2.5 YR 3 6 Dark red Abundant Most around 0.5mm, Very poor Mostly sub angular, some Quartz SiO2 Plagioclase NaAlSi3O8 – CaAl2Si2O8
few larger ones up to 2.0 mm larger rounded ones Calcite CaCO3 Olivine (Mg,Fe)2SiO4 15 Red with black edge on one side 2.5 YR (main) 2.5 YR (edge) 3 2.5 6 1 Dark red Reddish black Abundant 0.1 – 0.5 mm Very poor Mostly angular and sub angular Quartz SiO2 Olivine (Mg,Fe)2SiO4 Plagioclase NaAlSi3O8 – CaAl2Si2O8 Sanidine (K,Na)AlSi3O8 Unknown red mineral 16 Pale yellow 2.5 Y 6 6 Olive yellow Abundant 0.2 – 0.5 mm Fair Mostly sub rounded Olivine (Mg,Fe)2SiO4 (Mg,Fe)SiO3