104 Analysts of a Black Sand from the River Dee* 



from its properties, was oxide of titanium, slightly con- 

 taminated with iron. It weighed rs grains. 



6. The acid solution being concentrated by gentle eva- 

 poration, a number of small yellowish-coloured needles 

 made their appearance in it. By repeated evaporations, all 

 the crystals that would form were separated. They weighed 

 six grains. I redissolved them in water, and added some 

 ammonia to the solution. A fine yellow powder fell, which 

 I soon recognized to be oxide of uranium. Jt weighed 4*2 

 grains. 



7. Thus it appears, that the 52 grains (No. 4.) attracted 

 by the magnet contained 46 grains of iron, and six grains- 

 of uranium and titanium. 



8. The following are the substances separated from 100 

 grains of iserine, by the preceding analysis : 



Oxide of titanium. 

 Oxide of iron, - 

 Oxide of uranium, 

 Silica, 

 Alumina, 



Total, 12.5-0 



, Here is an excess of no less than 25 grains, to be ac- 

 cpunted ft^r by oxygen, which must have united to the 

 three metals during the process. As to the silica and alu- 

 mina, there can be little hesitation in ascribing them to 

 grains of sand, which had been mixed with the ore. The 

 pure iserine, in all probability, was composed of iron, ti- 

 tanium, and uranium. If we suppose that each of these 

 metals existed in the state of protoxide, we must diminish 

 the titanium by one-fourth, the iron by one-seventh nearly, 

 and the uranium, according to Bucholz's experiments, ty 

 •ne-fifth. This would give us. 



Titanium, 

 • Iron, 

 Uranium, 

 Silica and alumina 



103-9 



Here, tUeiir is still an e-icccss of nearly four per ecnti 

 JBut this I am disposed to ascribe to the oxides of titanium 

 iind uranium, having been only dried upon the steam-bath, 

 LTpon the whole, it appears, that in the specimens of iserin« 



analysed^ 



