aN 
96 Meteorice Stones. 
masses, and if the other parts of the moon are not so full of iron, 
then we see a reason why that point turns continually Lowen 
the magnetic globe of the earth. 
The mineral portion of meteoric stones consists of various min- 
erals. 1. Olivine. It contains magnesia and protoxyd of iron, 
is colorless or grayish, but is sometimes streaked with yellow or 
green like all the terrestrial olivine. This shows that oxygen 
is wanting for a higher oxidation of the iron. Like the terres- 
trial, it is soluble in acids, and leaves the silicious earth in the 
form of gelatine. . It contains like some of the terrestrial, a trace 
of oxyd of tin and oxyd of nickel. Olivine, however, in the me- 
teoric iron found by Pallas, makes an exception to this, for it is 
without nickel, and its color is yellow approaching to green ; but 
it contains tin. Olivine comprises about one half the quantity of 
the unmagnetic minerals. Olivine separates by treating with 
acids, and the silicious earth is then set free by boiling in car- 
bonate of soda. 
Then there remain, 2. silicates of magnesia, lime, an 
of iron, protoryd of manganese, alumina, potash, and soda, which 
are not separated by acids and in which the silicious earth con- 
tains two species of bisilicates. These are probably blended with 
more, which I was not able to separate. We may conjecture 
Mg 
a species of pyroxene f ¢ S? and a species of leucite where 
C 
lime and magnesia in the first terms replace a portion of potash 
Mg 
and soda. + S?4+3AS2. The pyroxene not having so much 
color as the terrestrial, is to be attributed to the same cause as the 
want of color in meteoric olivine. 
3. Chrome-iron.—This is contained in both kinds of meteoric 
stones, in both in like small quantity, isnever wanting, and is the 
source of the chrome in meteoric iton. It can be obtained unde- 
composed if the unmagnetie portion of the meteoric stone is sepa 
rated with hydro-fluoric acid, and is then, after all the silicious earth 
is removed, treated with sulphuric acid, after which the sulphates 
and the gypsum are boiled out, when the chrome iron remains 10 
the form of a black burnt powder. This is the cause of the grey- 
ish color in meteoric stones when they are seen in the mass. 
