150 THE PROSPECTOR'S HANDBOOK. 



To Find the Weight of Ore in a Lode, and Value 

 of a Property. 



To find approximately the weight of a quantity of ore in a 

 part of a lode (supposing the rectangular planes of surfaces 

 representing the boundaries of the lode are parallel). 



(Height x width x depth) in cubic feet X 1,000 oz. x 

 s.g. of ore, = weight in ounces of ore. 



Example : Find the weight of quartz in part of a lode 

 6 inches wide, 6 feet long x 6 feet deep. 



6 in. X 72 in. X 72 in. 

 Weight = - ' t g - x 1,000 X 2-5, 



= 18 cubic feet x 1,000 x 2-5, 

 = 45,000 oz. = 2,8 1 2 Ibs. approximately, 

 = a little less than i ton 

 (2,240 Ibs. = i ton). 



N.B 1,728 cubic inches make one cubic foot, and a 

 cubic foot of water = 1,000 oz. 



The reason that 1,000 is a factor in these calculations is 

 that 1,000 ounces is the weight of i cubic foot of water, 

 water being taken as the standard unit of specific gravity. 



N.B. In the case of quartz the number of tons in a lode 

 may be known approximately by dividing the cubic feet of 

 the lode by 15 (sometimes by less), as 15 cubic feet of 

 average quartz weighs about i ton, though theoretically it 

 might be 14, as in above example. 



To find the amount of ore and its value on a property, 

 let A c D B represent the horizontal surface of the property 

 and A B the direction of the outcrop of the lode along the 

 edge of it. 



