398 IVORY AND THE ELEPHANT 



Siberian mammoth tusks as shipped to-day, they are found 

 to average more than five times the size and weight of the 

 tusks from hving elephants. The superior weight and the 

 immense number of these mammoth tusks are clear indi- 

 cations at once of the extent of territory over which the 

 primeval elephant wandered, and of the great age to which 

 many or most of these animals must have attained. 



In this great collection of mammoth tusks many were 

 brown or yellow brown on the exterior. These are usually 

 the most compact in structure, and the ivory in the best 

 state of preservation; when the tusks are gray, or quite 

 white, they are more likely to be fractured, and broken, 

 and rough on the surface, with a superficial stringlike de- 

 composition. Occasionally they are indented with pits 

 from one to ten millimeters across and from one to four 

 or five millimeters in depth. These may be due to the 

 action of some vegetable acids. 



Part of the mastodon tusks had a coating of a dull blue 

 colour, due to the action of phosphoric acid in the seams of 

 the ivory, on coming in contact with some iron while the 

 tusks were buried. This material resembled odontolite, 

 or "bone turquoise" as it is called, more correctly "ivory 

 turquoise, " used in the eighteenth century. It is imdoubt- 

 edly vivianite, a phosphate of iron, occasionally met with 

 on battlefields, where horses' hoofs with iron shoes have been 

 buried with human and animal bones. 



Nearly all the mammoth tusks show more or less wear — 

 in some cases considerable wear — on the sides and at the 

 ends. This is evidently due to extreme use of the tusks in 

 digging up the soil in search of food. Mammoth ivory is 

 also occasionally stained a bright red, almost a blood red, 

 a stain produced by iron salts. Some of the ivory is very 

 fine and compact and will make piano keys of the first 

 quality, the colour being pure ivory white after treatment. 



