METALLIFEEOUS MINERAL LANDS. 145 



Survey, was the determination of the nonmineral character of a 

 " school section " on the .edge of the city of Tacoma, Wash. This 

 detailed examination was made in 1895 and resulted in the defeat of 

 the mineral claimant, who had attempted to obtain under the placer 

 law nonmineral land possessing large suburban value. As a result 

 of the decision the title to this land passed to the State of Wash- 

 ington. 



METHODS OF CLASSiriCATION. 

 AGENCIES BETPIiOTED. 



Classifications promulgated by the Survey are made by the metal- 

 liferous section of the land-classification board and are based on 

 data gathered by the field geologist and by him presented to the 

 section. Other geologists having special loiowledge of the area or 

 type of deposits under consideration may be called in, so that each 

 classification represents the best scientific and technical judgment of 

 the Survey. 



PBOBIiEMS mVOIiVED. 



Each classification of metalliferous land involves one or both of the 

 following problems: (1) Whether an alleged "discovery" of min- 

 eral constitutes valid ground for issuing a mining patent ; . (2) whether 

 certain lands are without value for their metalliferous minerals and 

 may therefore be patented under the laws relating to nonmineral 

 land. The first problem is typically presented where the propriety of 

 issuing patent to a mineral claimant is in question ; a typical example 

 of the second problem is that presented by the Northern Pacific land 

 grant. 



Evidently the first problem is the more concrete and the more 

 readily solved. In order to determine the validity of a specific min- 

 eral claim all that is necessary may be to find and identify the claim 

 and to estimate the value of the lode by sampling. The most difficult 

 cases, on the other hand, are probably those that involve the classifi- 

 cation of large areas in which little prospecting has been done. In 

 order to reach an intelligent conclusion in such a case evidence of 

 many kinds must be obtained, the gathering and effective presentation 

 of which may involve the making of a fairly complete topographic 

 and geologic map, a task which only a geologist can effectively 

 perform. 



In actual practice few cases present only one of the problems stated. 

 Even if the main problem is the first one it is usually desirable that 

 the examiner should learn something of the general geology of the 

 district; and ff, on the other hand, the main problem is the second 

 the apparent value of particular claims is an important part of the 

 evidence. It is not necessary or practicable, therefore, to separate 



78894°— Bull. 537—13 10 



