56 Description of A chmite, a new, Mineral . 
to Professor Mitseheiiicli’s measurements with the reflecting 
goniometer, 
M : M == 86® 56' 
M : r = 133 28 
M : e == 136 32 
■9 : s =s 35 0 
« :V? 162 30 
t : t = 28 19 
* : e = 165 15| 
The angle of the edge, t = 104° 26' 
And of the edge, s — 80°. otr — 140. 
The facets of the prism corresponding with'the cleavages are 
very perfect, but the terminal facets are less so, and therefore 
the above measures of their inclination may deviate a little from 
the true angles. It melts readily before the blowpipe into a 
black globule. 
This mineral occurs in the parish of Eger, in the south of 
Norway. It is found in nodules of quartz, disposed in a gra- 
nite, which, according to Hausmann and Von Buch, belongs to 
the transition formation, and the crystals appear to radiate from 
the granite into the quartz. 
According to the analysis of Professor Berzelius, this mineral 
contains 
Silica, . , 
55.25 
Oxide of Iron, 
31,2 
Oxide of Manganese, 
1.08 
Lime, 
0.72 
Soda, 
10.40 
99.70 
If the minute quantities of lime and manganese be regarded 
as replacing a corresponding quantity of soda, the formula re- 
presenting its composition is -=iNS 3 -f* 3 FS 2 -. 
As Hauy has derived the name of Axinite from the axe-shaped 
form of the crystal which bears that name, Berzelius has given 
that of Achmite (from a point) to this new and very re- 
markable substance # . 
* In the cabinet of Mr Allan, there is a large and well defined crystal of this 
substance, which he some years ago received as an unknown mineral from Norway. 
The particular locality was not given. It presents additional facets, not only on 
the edges of the rhomboidal prism, but on the summit of the acute pyramid. The 
latter are so small, that it is not easy to give their precise measurement. By ex- 
amining a fragment of this crystal, Dr Brewster found that it possessed double re= 
fraction in a very considerable degree.— Ec, 
