484 SYSTEMATIC DESCRIPTION OF PRECIOUS STONES 



Quite recently (about 1900) there has been found in this region an enormous amethyst 

 geode, a portion of which was shown by Herr C. W. Kessler, an agate merchant of Idar, at 

 the Diisseldorf Exhibition of 1902. It was found by the agate-seekers at an elevation of 

 600 metres above sea-level in the Serra do Mar, in the State of Rio Grande do Sul, and 

 about ninety miles north of the German settlement of Santa Cruz. The cavity was only about 

 a metre below the surface in a reddish clay, the weathered product of melaphyre, while the 

 lower portion of it still remains embedded in the solid rock. It measured 10 metres 

 (33 feet) in length, 5^ in breadth, and 3 in height, and was estimated to weigh thirty-five 

 tons ; about fifteen tons was shipped in ten pieces to Idar. The whole of the cavity is lined 

 with brilliant crystals of amethyst of a deep bluish-violet colour and averaging about 

 4 centimetres across. 



At a few localities in the State of Minas Geraes, in the northern poi-tion of Brazil, 

 where it is not associated with agate, the mineral has another mode of occurrence as groups 

 of beautiful crystals. These are found on the Campos dos Cristaes in the neighbourhood of 

 Diamantina, but the finest specimens come from the Ribeirao da Paciencia at Itaberava, 

 near Cattas Altas, south of the town of Ouro Preto (Fig. 67), where they occur under the 

 same conditions as the yellow topaz already described. In the gem-gravels of the district of 

 Minas Novas are many pebbles of amethyst accompanying the pebbles of white and blue 

 topaz, chrysoberyl, &c., already described, and which, like these, are probably derived from 

 granite and gneiss. 



In the United States of North America a certain amount of amethyst suitable for 

 cutting is found, none of which, probably, leaves the country. It is most abundant at Deer 

 Hill, near Staw, in Maine, but comparatively little of this is suitable for cutting. Good 

 crystals of large size, transparent and finely coloured, are met with in the State of 

 Pennsylvania, namely, in Chester County and other districts, but specially in Providence 

 Township, Delaware County. Fine specimens have been found in Haywood County, North 

 Carolina. The amethysts of Rabun County, Georgia, are remarkable in that they frequently 

 contain large fluid enclosures, those in other amethysts being of microscopic size. The 

 stone is widely distributed in the region of Lake Superior, especially on the Canadian side, 

 Amethyst Harbour being a typical locality ; but most of the material found in this district 

 is unsuitable for cutting. The amethyst of Nova Scotia is not infrequently used as an 

 ornamental stone, that from the Bay of Fundy and other places being often worked into 

 objects of considerable size. 



Another American locality still to be mentioned is Guanaxuato in Mexico. The 

 crystals found here measure as much as a foot in length ; the prism is usually pale in colour, 

 the pyramidal termination alone being of a deep shade, and, moreover, the crystal as a 

 whole is seldom transparent enough for cutting. Far finer stones than those found at 

 Guanaxuato are frequently found in the ancient Aztec graves, so that there must be other 

 localities in Mexico now unknown. 



The amethyst pebbles found in the gem-gravels of Ceylon, being the finest known, 

 superior even to Brazilian stones, are much in demand. They have been derived from the 

 granitic and gneissic rocks of the neighbourhood, and occur with the other precious stones 

 mentioned under ruby, with which they are collected in the manner already described. 

 Amethyst occurs in the same way in a few of the rivers of Burma, also in small amount in 

 India, but in neither country has the occurrence any importance. 



The amethyst localities in the Urals, on the other hand, are extremely important, 

 especially the neighbourhood of Mursinka in the Alapayev and Reshev mining districts, in 

 the Ekaterinburg division of Government Perm, the village of Mursinka being in latitude 



