NATIVE COPPER, ABORESCENT AND CUBICAL. 31 



native copper at the mines of BaHymurtagh, in the county of 

 WicMow. At the depth of about 300 feet, in cutting a drift 

 from south to north, to meet the valuable lodes of copper ore, 

 to the west of the old works, a fissure was discovered running 

 diagonally across the lodes, and bearing about north north-west, 

 while the lodes ran from east north-east to west south-west 

 and were three in number perfectly parallel with well-defined 

 walls, but varying in their rftp; so that the most southern, having 

 less head, or being more perpendicular, unites with the others 

 at given depths, the mineralized strata, hard killas, or argilla- 

 ceous ground with mica schist, and mineralized sulphur. The 

 fissure was filled with black oxide of copper granulated like 

 coarse gunpowder, and mixed with quartz crystallized like very 

 large sand. The fissure was frequently closed with a large 

 solid deposit of quartz, in the body of which we usually, and 

 almost on every occasion, found cavities of about eighteen 

 inches high, six to nine inches wide, and from two to three feet 

 in hwizontal length. These cavities were surrounded by quartz 

 crystallized in a beautiful manner ; they were also usually half 

 full of quartz in loose detached crystals, with very small por- 

 tions of oxidized copper, but having many beautiful bright 

 specimens of native copper, in a perfectly pure metallic state, 

 some of which were arborescent, like the heath, with here and 

 there a few cubes of native copper attached. There were also 

 some specimens in the form of flat narrow riband, about the 

 tenth of an inch wide, and eight or nine inches long, the thirty- 

 second part of an inch thick, having at regular distances, of 

 about the tenth of an inch, the most perfect cubes of nearly 

 one-tenth of an inch square, all connected with the flat or ri- 

 band-like base. They were of the brightest rose colour, and in 

 the most brilliant state as to their surfaces ; and on exposure 

 to the atmospheric air resisted for some days the usual oxidation, 

 and when cut they were found to bepure copper in a solid state. 

 It would appear that where the oxide of copper was in abun- 

 dance the native copper was not to be found in the open parts 



