. Manual of the geology of Ireland. f black sand, as the rocksare crumpled, as they designate the twisting and bend-ing of the lines of lamination to the fault lines. Whenone of these fault lines meets cross joints, hollows occur, inwhich there is more gold than elsewhere in the run ; asthese cross joints are more or less systematic, the spotsin which the gold is found form regular patterns, some-what like the corners of the squares on a chess-board. Thegold usually occurs as Eyesills or minute scales, but in somelocalities as large gold, or grains; while nuggets or * In places the bed rock is
. Manual of the geology of Ireland. f black sand, as the rocksare crumpled, as they designate the twisting and bend-ing of the lines of lamination to the fault lines. Whenone of these fault lines meets cross joints, hollows occur, inwhich there is more gold than elsewhere in the run ; asthese cross joints are more or less systematic, the spotsin which the gold is found form regular patterns, some-what like the corners of the squares on a chess-board. Thegold usually occurs as Eyesills or minute scales, but in somelocalities as large gold, or grains; while nuggets or * In places the bed rock is rounded and smoothed, evidently by water, asno trace of ice stria? could be found on the rocks or on the blocks contained inthe overlying drift. Mines and Minerals. 345 large lumps are found from time to time; the heaviestnugget weighed 21*5 ounces, while others have been foundof 18, 11, and less weights. The sand in the runs isharrowed out and washed in Long Toms, or narrow,shallow, wooden troughs, at the streams, and the residue. Gold washing, Gold-mine Valley, Wicklow. panned ; formerly cradles and wide buddies were used,but the small quantity of gold in the stuff made the opera-tion tedious and but little profitable. According to Weaver the following minerals occur withthe gold : magnetic iron, sometimes in pieces of half a 346 Geology of Ireland. hundred-weight ; titaniferous iron ; specular, red andbrown ores ; pyrite; tin ore associated with wolfram ;manganese ore; garnets ; quartz; and ripidolite. Tothis list Mr. Mallet has added {Jour. Geol. Soc. iv. p. 271): platinum ; galenite ; chalcopyrite ; molyb-denite ; sapphire; topaz ; zircon ; and spinelle. Malletgives a very large return of tin ore (3*5lbs. from sand), while all others observers have found very littleof it* In the old working (Ballinasilloge) more tinoccurred than higher up (to the SW.) in Ballinavally. Most of the gold seems to be abraded and more or lessworn by attrition, but some of it
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