Geology of the Good Hope

features of the area. Sills of hornblende-porphyritic clioritc, are part of the Hedley Intrusive suite believed to bc Latf Triassic or Early Jurassi.: (199 Ma based on U-Pb dates 0 ' zircons from the Banbury stock, 3.5 kilometres west o' Hedley). In this location the sills, which vary.from I to 2f' metres in thickness, make up almost 50 per cent '3f thl: stratigraphic column whtxe they intrude laminated lirnmtonl: and siltstone of the Hedley formation. They occur bot11 adjacent to the Toronto quartz diorite tcl gabbro stock ,md a i far away as 2 kilometres from it. Aurife!rous skam mineraliz ation is spatially and genetically associa1:ed with the st'ock an1 I the adjacent diorite sills (Billingsley and Hume, 194 1; Dol. mage and Brown, 1945, Ray et al., 1986, 1987, 1'288). i. similar sill swarm is developed within the French Mint: formation at the French mine and a single sill is asscciatell with mineralization at the Good Hope mine.