CORUxVDUM (SAPPHIRE): OCCURRENCE IN AUSTRALIA, EUROPE 291 



consisting of niica-augite-andesite, crystals of sapphire, garnet (pyrope), and sanidine have 

 been found ; and it has been argued from this that in every case the sapphires origiriated in 

 similar situations and have been set free by the weathering of the igneous rock. This origin 

 for the sapphire is not universally accepted, although parallel cases may be found in the 

 occurrence of fine blue sapphire in the volcanic rocks of other regions, such, for example, as 

 the basalts of Unkel on the Rhine, Niedermendig on the I^aacher See, Calvarienberg near 

 Fulda, and Expailly near Le Puy-en-Velay in France, &c. 



More recently sapphires have been found at Yogo Gulch in Fergus County, also in the 

 State of Montana, and seventy-five to one hundred miles east of the Missouri bars. According 

 to G. F. Kunz and others they occur here in a yellow earthy material, which also may owe its 

 origin to the weathering of an igneous rock. The blue stones vary in shade from light to 

 dark, some being of the true sapphire or cornflower-blue, while there are others which incline 

 to an amethyst or almost ruby shade of red. The crystals are rhombohedral in habit, and 

 in this respect differ from the sapphires found near Helena. 



The amount of corundum of a quality suitable for cutting which comes into the market 

 from Australia is not altogether insignificant. The mineral is found in gold-sands with 

 diamond and in stanniferous and other similar sands and gravels in Victoria, South Australia, 

 Queensland, and especially in New South Wales. In the last named State, sapphires are 

 found in the north-east corner in the New England district, especially in the neighbourhood 

 of Bingera and Inverell, and indeed at all the localities which have been already mentioned 

 for diamond (Map, Fig. 43). Sapphire occurs here under exactly the same conditions as 

 does the diamond, and it is even more widely distributed. An occurrence of the stone in 

 Tasmania has also been recently reported. 



Australian sapphires, as a rule, are too dark to be of much value as gems ; they vary 

 from perfect transparency and absence of colour through various shades of blue and grey to 

 almost absolute opacity and dark blue colour. Crystals showing a fine sapphire-blue colour 

 are met with occasionally, and fine star-sapphires are not uncommon. A few rubies are 

 found, but corundum of a fine green colour, that is " oriental emerald," is more abundant, 

 every hundred stones always including two or three specimens of " oriental emerald." The 

 original crystalline form of the stones, a hexagonal bipyramid (Fig. 53, e, &c.,) is frequentlv 

 well preserved, but more often they are in the form of irregular grains or rolled pebbles, like 

 the other constituents of the sands. From a commercial point of view the Australian 

 output of sapphires is unimportant. 



In Europe a well-known and often mentioned locality for sapphires is the Iserwiese, 

 the district in which is the source of the Iser river, which drains the Iser mountains in 

 northern Bohemia. Sapphire, together with ceylonite, zircon, garnet, and iserine, is found 

 here in loose, alluvial material derived from the weathering of granite. The sapphires 

 sometimes occur as small hexagonal prisms, but more often as water-worn grains of various 

 shades of blue and with various degi-ees of transparency. While pale blue stones are 

 usually cloudy and opaque the darker ones are, as a rule, transparent. Single sapphires of 

 the finest quality are said to have been found here, all, however, of small size ; stones qver 

 4 carats in weight are extremely rare. The deposit, never very extensive, has been 

 systematically worked for many years and is now practically exhausted. 



Single stones suitable for cutting have also been found in the garnetiferous sands of 

 Meronitz in Bohemia, in the auriferous sands of Ohlapian in Transylvania, of the Urals, of 

 Madagascar, of Borneo, and of some other regions. It is, however, unnecessary to give a 

 detailed account of the occurrence at these localities since in each case the stones are present 

 in such small numbers. 



