302 Adventures in Scenery 



No Gold in Volcanic Emanations 



No gold has been found in volcanic emanations, or in the 

 products of the same. What are known by the terrific name 

 pneumatolytic deposits that is, deposits formed from hot va- 

 pors or superheated liquids under pressure frequently contain 

 gold of economic importance. From this it has been inferred 

 that plutonic emanations molten rock poured out from fis- 

 sures or vents in the earth's crust contain gold, but it has not 

 been proved. 



Primary gold in metamorphic rocks has been found in only 

 two recorded instances. 



Gold Occurs in Sea Waters in Variable 



Amounts; Not in Fresh Surface Waters 



Determinations of the gold content of sea waters show an 

 extreme irregularity and wide variation in samples taken from 

 widely separated seas. Eleven determinations of gold in sea 

 waters gave an average value of 1 2/3 cents per ton. The ex- 

 treme irregularity or variation of the gold content of sea waters 

 is as noticeable as in the case of igneous rocks. 



Gold has not been detected in fresh surface waters, but its 

 presence in ordinary surface waters is inferred from the fact 

 that gold has been detected on the roots of plants and trees. 

 The absorption of gold from solutions by growing plants has 

 been experimentally proved. Ashes from trees that grew in a 

 gold-bearing region contained gold. Coal has been frequently 

 found to be auriferous (gold-bearing). A Wyoming coal is 

 stated to contain gold of a value of $1.00 to $5.00 per ton. 

 Ashes from Utah-Wyoming coal is reported to yield 60 to 80 

 cents value per ton. 



Gold-Bearing Veins Formed from Heated 

 Waters from Great Depths 



Gold has been identified in circulating waters of the earth's 

 crust. Heated waters rising from great depths are known to 



