Geology of the Diamond Creek Area. 353 



EXPLANATION OF PLATES. 



Plate XXV. 



Geological sketch map of the Diamond Creek area; the alluviuin of 

 the Yarra not shown ; also longitudinal and transverse sec- 

 tions at the Diamond Creek mine. The longitudinal section 

 is published by permission of Mr. Christian. 



Plate XXVL 



Fig. 1. Photomicrograph of the fine-grained basalt analysed, x 25, 

 ordinary light, with a felspar phenocryst in the field of view. 



Fig. 2. Photomicrograph of the breccia, Diamond Creek mine, x 

 8, ordinary light, S = sandstone, SI = slate, C = calcite, 

 Sh = shale. Secondary quartz and calcite veins intersect 

 the rock. 



Fig. 3. Microphotograph of a gold-bearing dyke vein, x 25, 

 ordinary light, showing the contemporaneous origin of the 

 gold, quartz and .stibnite. Q = quartz, G = gold, S := 

 stibnite, P = pyrite, Se = senarmontite, D = dyke. 



tig 4. Microphotograi^h of gold-bearing quartz from the -300 feet 

 level of the Diamond Creek mine, x 25, ordinary light. 

 The secondary character of the ffold is well shown. 



