61 



Case 85, 1799 was originally quite like 1794, but was partially converted 

 into oxide, while still retaining its crystalline form, at the great 

 fire which destroyed the museum eollectioos in 1882. 



3936, a nodule of azurite that has been cut and polished to 

 reveal the concentric and radial structures better : it would be 

 an attractive ornamental stone. 



Sulphide Ores. — The sulphide ore found beneath water-level 

 consists of copper pyrites and copper glance,* principally the 

 former. 



8936 shows veins and patches of copper pyrites in a dark-green 

 slate. 



New Mount Hope. — Giqjrite, azurite, and maJacTiite occur as 

 at Cobar, and are sometimes well crystallised (1793 and a fine 

 mass of azurite crystals kindly lent to the Museum.) The 

 country rock is somewhat similar to that at Cobar, but the ore 

 occurrence is different. 



1785, bleached country rock in more or less parallel strings. 



1793, malachite in sandstone. 



1833, copper pyrites. 



GiRiLAMBONE. — Here, as at New Mount Hope, the ore occurs, 

 not in true lodes, but in veins traversing the slatesf and sandstones 

 of the country. 9152, slate traversed by irregular veins of 

 copper pyrites. 8924 and 8925, in upright case 128 near the 

 entrance, show the copper ores (carbonates and sulphides 

 respectively) deposited between the separation faces of the 

 schistose country rock. Native copper (1558), malachite (4177), 

 and azurite (1776) occur above water-level. 



Nymagee. — The massive character of the ores will be noted :— 

 Cuprite (8177), copper glance (1837), copper pyrites (6967). 



* Copper glance or redruthite contains copper combined with sulphur, and is a richer ore 

 than copper pyrites. It is a massive mineral, breaking with an even fracture, and fre- 

 quently escapes notice as a copper ore owing to its black colour. It can be readily identified 

 by the ease with which small shavings may be cut from it with a penknife, leaving a shining 

 surface (sectility). 



t The slates have sometimes been transformed into schists. 



