——ar 
J. L. Smith—Association of Garnet, Idocrase, ete. 435 
is perfectly pure, as shown by the following analysis of a por- 
tion from which the calcite was carefully separated : 
Be ee ee ee a ee ee 38°02 
Horacie acid 2. Sik eee eae 21°62 
Re oS 33°87 
WRG 56s 2 ks 5°61 
99°12 
The association of this mineral with garnet and idocrase is, I 
believe, now mentioned for the first time. 
The garnet is the variety cinnamon stone; the crystals are 
over the exterior, and are cinnamon-colored within or through 
the mass of the crystals; sp. grav. 3°59. An analysis of the 
Silica 42°01 
Alumina. .-.... 17°76 
Sesquioxide of iron 5°06 
Oxide of manganese. > _..-..... 2-2. ---- 20 
Taine BO i ee ee 35°01 
Matinee eo ee 13 
100°17 
that it is impossible to say where the idocrase terminates and 
the garnet begins. A large crystal of garnet, when cut in two 
and polished, shows the idocrase penetrating it, like so many 
st 
green streamlets through the interior. Its specific gravity is 
3445. A portion carefully separated from the garnet gave the 
following results : 
aoe oo awe SO OU 
Alena eee 17°04 
Sesquioxide of iron a eee 
Oside’ oF ininssiens. 0 2 18 
MB. SS Be 35°94 
Magnesia ee ee 1°07 
Woteeh 2S es ee 51 
iis by bestictl i206. oe 2°00 
99°23 
I know of no locality where the above minerals are associated 
m the manner described. The fact respecting the garnet and 
