NOTES ON COLLECTING MINERALS. 



From the collector's point of view, Minerals differ in many respects 

 from both Animals and Plants : the individuality being little pro- 

 nounced, a specimen may be broken in two, and yet often be as 

 satisfactory as before in its illustration of the characters of the 

 material ; the characters themselves are independent both of climate 

 and seasons and of mere longitude and latitude ; the material, after 

 collection, is comparatively permanent, and is free from that liability 

 to decay which is a special feature of organic matter. 



Meteorites. — Of the mineral products of Nature some are interesting 

 as having fallen from the sky (meteorites) : most of these (meteoric 

 stones) are of grey stony matter, which is completely covered with a. 

 thin black crust, and contains particles of metallic iron dispersed 

 through it ; the others consist of metal (meteoric iron), which, though 

 containing on the average about 10 per cent, of alloyed nickel,, 

 has an aspect like that of the iron of commerce. As native iron 

 is extremely rare, any natural material consisting either wholly 

 or partially of metallic iron is of special interest and worthy of 

 collection. 



Minerals. — The specimens which show the characters pertaining 

 to mineral species and varieties in the most perfect way are found, 

 not at the earth's surface, but in the course of the working of mines 

 and quarries. The people connected with the latter know when a 

 specimen has unusual merit, and they are in more or less direct 

 communication with mineral dealers; specimens of exceptional 

 character thus already find their way from these districts into the 

 market, and a traveller without special knowledge of minerals can 

 be of little help. 



Rocks. — In general, rock-specimens are of little value, except in 

 connection with a complete survey and description of the region by 



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