46 KEMPS ORE DEPOSITS. 



are the principal illustration of economic prominence. The attri- 

 tion veins are an important class, and increasing study has wid- 

 ened the application of this or synonymous terms. Segregated 

 veins and true veins are well-known forms. ' In the comments of 

 Von Cotta, which follow Von Weissenbach's paper, veins are 

 grouped from every possible standpoint, Von Weissenbach's 

 scheme being taken as the one based on origin. Nos. 2 and 4 have 

 small claims to attention. No. 3 foreshadows the drift of many 

 subsequent writers. The meanings of the terms are self-evident, 

 except perhaps Gangzuge (linked veins). This refers to a group of 

 parallel and more or less overlapping veins, deposited along a 

 series of openings, evidently of common origin. It is a convenient 

 term. 



The terms used by Leconte may be passed without comment 

 as being self-evident in their meaning, except (4) and (6). The 

 scheme was devised, as a perusal of the citation will show, after 

 the author had set forth some original views of the causes which 

 lead to the precipitation of ores, and had forcibly stated others very 

 generally accepted. In the explanatory text some quite curious as- 

 sociations are found, which are cited by way of illustration. Thus 

 under group (4), stalactites, caves, gash veins, and the Leadville ore 

 bodies are considered examples, and under group (6) the grouping 

 together of beds, igneous masses, and all other forms of so-called 

 irregular deposit is decidedly open to criticism. This is the more 

 emphatic because the concluding sentences of the paper (of whose 

 general value and excellence there can be no question) give the im- 

 pression that the author felt he had cleared up all the points in the 

 origin of ore bodies which would be of interest or importance to a 

 purely scientific investigator as contrasted with a practical miner. 



1.06.06. B. General Schemes Based on Form, 



(6) 



Von Cotta and Prime. Ore Deposits, New York, 1870. 

 I. Regular Deposits. 



A. Beds. 



B. Veins. 



(a) True (Fissure) Veins. 



(b) Bedded Veins. 



(c) Contact Veins. 



(d) Lenticular Veins. 

 II. Irregular Deposits. 



