140 ORIGIN AND MODE OF OCCURRENCE OF GOLD-BEARING VEINS. 



and as the lode is one that holds out every reason to believe it to 

 be continuous in depth, good results may therefore be expected 

 in return for judiciously spent capital. This vein appears to 

 belong to the true fissure lode class, and is a good example of 

 such kind of vein. Fig. 9 is a section of a part of the vein below 

 the water level, taken by the writer. This lode seems to have been 

 faulted, but not heaved, and this characteristic may have much 

 to do with the continuance or otherwise of the shoots of gold 

 in it. 



Gold veins occur in diorite and other igneous rocks in many 

 places throughout the colony, and those in diorite are generally 

 found to be very rich. 



At the head of the Temora alluvial gold-field, which has been 

 one of the richest ever found in the colony, is a rather low diorite 

 hill which forms part of a large dyke or intrusive mass of that 

 rock. This hill splits the upper part of the alluvial lead into two 

 branches, and it is evident that the numerous reefs that intersect 

 this hill have done much towards supplying the lead with its 

 gold. Some of these veins are of a large size, and they all contain 

 gold. So many reefs occur in this small hill that a 40-acre block 

 of land on it contains the portion of seven of them. 



The following sketch-plan (Fig. 31) shows the manner in which 

 they intersect the hill at the surface, and the section (Fig. 30) is 

 taken from one of the principal veins called the " Mother Shipton 

 Reef." This reef has yielded in one part as much as 

 800 ounces from 2cwt. of quartz, and one piece of gold taken from 

 the reef weighed 328 ounces. This magnificent specimen was 

 sent to the Indian and Colonial Exhibition, and has since been 

 presented to the Queen. 



The quartz in this vein is tightly contained within the diorite 

 walls and is largely charged with iron pyrites, as is also the walls 

 of the lode for some distance from it. In the upper portion, near 

 the surface, the walls close to the vein are much decomposed and 

 completely filled with cubical cavities containing iron oxide from 

 the decomposition of the pyrites. Both the croppings of this lode 

 and the alluvial deposits close by contained a large quantity of 

 gold, and the soft decomposed country along the junction of the 

 diorite and the slate, which occurs close to the lode as shewn on 

 plan, contained a number of narrow veins of quartz very rich in 

 gold. 



The lode has been heaved into the foot- wall three times in a 

 depth of 100 feet, and some of the richest patches were obtained 

 from near where the vein was broken by the heave or slide. The 

 width of the lode is from a few inches to nearly two feet, having 

 an average of about eighteen inches ; in some parts the quartz is 

 crystallized. 



