BULLETIN 39, UNITED STATES NATIONAL MUSEUM. 



[4] 



removed and the size of the specimen reduced by means of a few small 

 chisels and cleaning tools (see figs. 3-6) and a trimming hammer (see 

 fig. 2). The trimming hammer should weigh from a quarter to half a 

 pound, and have both faces square. By holding the specimen firmly in 



the left hand and delivering a sharp 

 blow with the hammer the gaugue 

 rock maybe removed wit;hout injury 

 to the mineral. A pitching tool 

 (fig. 6) is useful in shaping the speci- 

 men after trimming. The other 

 tools needed are three steel chisels, 

 one six inches long (fig. 5), the 

 others three inches long, and of 

 similar pattern, for cutting x^ur- 

 poses ; a set of steel wedges for split- 

 ting rocks, and a pickax to remove 

 surface material and for prying. 



In many cases it is necessary to 

 blast. Blasting iDowder, drills, 

 sledge hammers, fuses, etc., may' 

 sometimes be carried, but they can 

 commonly be borrowed from miners 

 or quarrymen, who can also be hired 

 to assist in the work. Avoid heavy charges of powder, in order that 

 the material sought for may not be excessively shattered. The opera- 

 tion of blasting, regarded from the standpoint of the mineral collector, 



Fig. 1. 



Collecting hammers. 



Fio. 2. 



FlQ. 3. 



Fig. 4. 



Fig. 6. 

 Cleaning and pitcliing tools. 



requires the greatest care and judgment. A fine locality may be ruined 

 by the reckless use of dynamite. 



