100 E. T. Allen — Native Iron in Missouri* 



stone was reached. In 1S95 it dried up for the first time. 

 Accordingly the owner decided to deepen it. After drilling 

 through fourteen feet of solid sandstone, the iron was struck 

 at a depth of fifty-one feet. An eight-inch drill and a five 

 hundred pound beater were employed, but so refractory was 

 the vein (or pocket) that the workmen gave up the attempt to 

 penetrate it. On learning from us the nature of the substance, 

 small portions of which were brought to the surface, the work 

 was continued, but it required over half a day to go through it. 

 The workmen judged the thickness of the vein or pocket to be 

 five or six inches. Solid sandstone was found again on the 

 other side of the iron, into which the drilling was continued 

 for twenty-three feet, when the water rose to the same height. 

 We learned on inquiry that no coal or shale was found in the 

 boring although the place is in a coal region and coal has been 

 discovered within five miles. 



Examination of sandstone. — The sandstone matrix of this 

 natural iron was of a very light brown color and of moderately 

 fine grain. It possessed a calcareous cement amounting to 

 over thirty per cent of its weight, a little iron in the form of 

 ferric oxide and small quantities of alumina. A microscopic 

 examination of a small portion which had been treated with 

 hydrochloric acid showed that the residue consisted almost 

 entirely of quartz grains. An analysis yielded the following 

 results : 



Insoluble in hydrochloric acid 64*14 



[Of this 63-52 per cent = Si(X] f CaC0 3 30-90 



| MgC0 3 ______ -89 



Soluble in hydrochloric acid { -p 2 ^ 3 ] , 2 2 



99-85 



The sample of sandstone was considerably crumbled when 

 we received it. From the crumbled portion we extracted a 

 large number of bits of metallic iron with the magnet. 



The metal. — The majority of these pieces, both those con- 

 tained in the crumbled sandstone and those received separately, 

 were flattened and irregular in shape, often hackly around the 

 edges and weighed about half a gram. When they reached 

 the laboratory all were slightly tarnished or coated with a thin 

 film of rust, but when first taken from the ground no rust was 

 visible, we were informed, though none of the pieces were 

 bright except where fresh fractures had been made by the 

 drill. The resistance which the iron offered to the drill showed 

 that there was a solid mass imbedded in the stone, and this 

 mass was evidently beaten to pieces. The iron was so malle- 

 able that it could be beaten out cold on an anvil to very thin 

 plates, though not without cracking somewhat on the edges. 

 Its hardness was just about that of fluorspar, the minerals 



