484 Transactions. 



identified as such by Professor Ulrich. Mr. Charles Reid, of 

 Windsor, has cut some specimens of these. They were obtained 

 from a gold-miner who worked in Slaty Creek, a tributary of the 

 Kakanui, which enters it some fifteen miles from its mouth. 

 A superficial search revealed no indication of them in the gravels 

 of this stream. The stones are of fair size, but of poor colour. 

 The second mineral is of a jasperoid nature. It has been traced 

 to Red Hill, near Elderslie, in the property of Mr. Menlove. 

 Green, yellow, and red bands may be obtained, and no doubt 

 polished ornaments might be made of them. The mineral seems 

 to form a large dyke, but more work is necessary on this point. 

 The third occurrence, the " gem gravels " proper, were found to 

 occur chiefly on the beaches south of Kakanui Heads. A recent 

 bed of marine gravel covers large areas of land, and the " gem 

 sands " may be obtained by panning off this gravel. They have 

 been found as far north as Oamaru Cape. No trace of them 

 has been found up the Kakanui or Waiareka Rivers. These 

 sands are similar to the Museum specimens, and may now be 

 briefly described. Besides pebbles (quartz), they contain small 

 cleavage fragments of hornblende and feldspar, clear green 

 minerals (presumably pyroxenes or amphiboles), red minerals 

 (presumably garnets) ; the two latter minerals being angular 

 and fractured, but showing no crystalline form. On the beach 

 between this stream and Kakanui South Head the sea has con- 

 centrated the sands so that thev consist almost entirely of 

 garnet and magnetite, forming a thin layer on the top of the 

 ordinary beach sand in a similar manner to the black sands 

 (magnetite) occurring at many places on the east coast of Otago. 

 The beach is periodically worked by a gold-miner, who scrapes 

 off the top layer and washes it in a cradle for gold. It was 

 believed by many of the residents of the district that occasionally 

 rubies were obtained with the gold, and that they fetched a good 

 price. The matrix was found to be a volcanic breccia occurring 

 both on the North and South Head at the mouth of the Kakanui 

 River. All the minerals of the " gem sands " were found in it, 

 with the exception of the magnetite and quartz. These, however, 

 are of such universal occurrence on the east coast of Otago that 

 it is unnecessary to specially consider them here. A general 

 description of the breccia and its relations is given. Detailed 

 accounts of the minerals and fossils are withheld till further 

 investigation has been made. 



General Occurrence. 



The breccia, for convenience called " mineral breccia," 

 occurs at four or five separated points in the neighbourhood 



