Fig. S1. The Highland Border Complex, NE Scotland, revisited: its role in Laurentian rifting, Early Ordovician emplacement and later faulting at the Highland Boundary

Fig. S1. Photomicrographs of chromites from North Esk and Kirkton compared with chromites in Loch Lomond clastics. (a) Euhedral brownish chromite with strong internal reflections from the Green Conglomerate, east bank of River North Esk, plane-polarized light (PPL), sample NE4A, 60326. (b) Broken, altered chromite crystals within chloritic grains, separated by angular quartz grain, from Green Conglomerate, with angular quartz grain between, east bank of River North Esk, PPL, 10x 2.4x sample 60328. (c) Four small probable chromite crystals within chloritic mass, from Basaltic-Terrigenous-Chert, PPL, 40x3x sample NE104. (d) Altered originally euhedral chromite grain with chloritized grain from Greenstone Conglomerate Kirkton of Balfour, PPL, sample #60317 GE25A x10x2. (e) Broken altered chromite grain (centre towards top of image), brownish within chloritized mass from Loch Lomond Shore, Arrochymore Point, Balmaha, PPL, sample 67484 x4x4 Image #4759. (f) As for (e) above with crossed nichols, sample 67484 chromite x10x2. (g) Close-up of broken chromite grain as for (e) above, PPL, sample 67484 chromite x10x2 xn. (h) Broken and altered chromite grain from Loch Lomond clastics (sandstones), Arrochymore Point, Balmaha, PPL, sample 67484 x40x2.