October 1, 1912.J 



THE INDIA RUBBER WORLD 



17 



Mineral Rubbers. 



AN ARTIFICIAL OR MINERAL RUBBER. 



NEARLY six years ago the English manufacturers of rub- 

 ber goods became deeply interested in a new substitute 

 for the natural caoutchouc. An English inventor be- 

 lieved that he had hit upon a method of turning wheat into 



that r'linmodity, so rapidly srowiuR scarcer. This in spite of 



F.xrosED Side or Ei.aterite I.epge. 



the fact that over three hundred patents had, up to that time 

 been taken put in the British Patent Office on substitutes for 

 rubber. But somehow or other the new substitute failed to gain 

 the place in the rubber world that was expected of it. 



Now it seems a bit curious that men of an inventive turn 

 ■should have thus been racking their brains when there lay 

 •to their hands a mineral substance, commonly known as 

 ^'mineral rubber," which, even in its raw state had many of 

 the characteristics of crude rubber. Elaterite is the scientific 

 name for this substance. In color, elasticity, and other quali- 

 ties it brings strongly to mind the distinctive characteristics 

 of India-rubber. It was first discovered at Angers, in France. 

 Later deposits were noted at Castleton, in Derbyshire, Eng- 

 land, in the lead mines of Odin, at Alteland, South Australia, 

 in Wasatch County, Utah, and elsewhere. The Wasatch de- 

 posits will be considered presently in another connection.. 

 In the Coorong district of South Australia a substance is 

 found which, known as Coorongite, is believed by some to 

 be practically the same as elaterite. Other chemists declare 

 it is a vegetable product; the genuine elaterite being a min- 

 eral substance. This elaterite varies, accor'ding to the locality 

 in which it is found, in quality and consistency. Sometimes 

 it is as thick and unyielding as frozen tar. Commonly, how- 

 ever, it is fairl}- soft, and sticky. It is a hydro-carbon, gen- 

 erally dark-brown in color. Sometimes it goes under the 

 name of elastic bitumen. Though so closely resembling rub- 

 ber, practical chemists found no way of putting it to commer- 

 cial use in that line, though other valuable uses had been 

 found for it. All at once, however, this situation was changed 

 with the finding of a new substance, now called tabbyite, in 

 Wasatch County, also the home of elaterite. This peculiar 

 name was given the substance in honor of old Chief Tabby, 

 of the Unita Indians, who directed chemists to this impor- 

 tant find. 



Elaterite, it has been said, is a hydro-carbon. Tabbyite is 

 also a carbon, belonging to the resinous group. A combina- 

 tion, or, rather, an amalgamation of the two appears to have 



formed an artificial rubber, difficult to distinguish from the 

 genuine. .'\ chemical analysis shows the following propor- 

 tions of constituents: Carbon, 87.12 per cent; hydrogen, 12.88 

 per cent. The essential characteristics of rubber are also 

 there, such as elasticity, texture, color, etc. If the compound 

 be touched with fire the odor of burning rubber very promptly 

 offends the nostrils. 



In making this compound two parts of elaterite to one of 

 tabbyite are used. 



The finer grades of rubber, it is true, have not been pro- 

 duced. The chief material so far manufactured has been for 

 matting, belts, insulation covering, etc. 



SOME TYPES OF MINERAL RUBBER. 



Tl Hi term "mineral rubber" .is used has but little significance 

 in determining the quality which it represents. The base 

 of practically all known so-called mineral rubbers is asphaltic. 



Mineral rubber should be classified in such a way that the 

 chief characteristics could be easily distinguishable, so that a 

 manufacturer could determine which one would be most suitable 

 for the purpose for which he might want to use it. In making 

 such a classification the essential qualities of each different grade. 

 both physical and chemical, should be determined. 



For a manufacturer to take one quality of mineral rubber and 



-An El.\tekite \'ei\. 



expect to use it in different grades of compound that he may 

 wish to make, with equally satisfactory results, is as much folly 

 as it would be to take one grade of any other ingredient that he 

 wishes to incorporate in a compound and expect it to work as 

 well in one compound as another. 



