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DESCRIPTIVE MINERALOGY. 
Pyrenaite ,or Pyreneite. Black or greyish-black and opaque. It occurs in small dodeca¬ 
hedral crystals, which externally have a metallic-like aspect. 
Aplome. Resembles garnet in aspect and external form, but differs in having its planes 
striated parallel with their lesser diagonal; which, according to Haiiy, indicates the cube as 
its primary. 
Grossular , or Grossulaire. Of an olive green colour ; translucent or semitransparent, and 
occurring in trapezoidal or leucite-formed crystals. 
Magnesian Garnet. Occurs massive, and in dodecahedral crystals variously modified. It 
is slightly translucent on the edges, and has a deep hyacinth or brownish red colour. It con¬ 
tains a large proportion of the protoxide of manganese. 
Melanite. This includes the velvet-black, opaque specimens. It occurs in rhombic dode¬ 
cahedrons, whose edges are often replaced. Before the blowpipe, it yields a brilliant black 
globule. 
Colophonite—Garnet Resinite. This is composed of rounded grains of various sizes, which 
may be easily separated. It is of a brown, red or yellow colour, and has a high resinous or 
resino-adamantine lustre. 
Allochroite. It has a greyish, dingy yellow or reddish colour; a glimmering lustre, and 
feeble translucency. It is massive, and has an uneven fracture. 
Pyrope. This variety occurs in roundish or angular grains of a deep blood-red colour, and 
perfect transparency. 
Topazolite—Yellow Garnet. This has a topaz-yellow colour: translucent or transparent. 
Occurs crystallized. 
Essonite, or Cinnamon Stone. Occurs in granular distinct concretions, and massive. It is 
of a hyacinth or orange-yellow colour ; transparent or translucent; has a resino-vitreous 
lustre, and a conchoidal fracture. Phillips describes this as a distinct species. 
Chemical Composition. This is of course somewhat different in the different varieties. 
Almandine from New-York —Silica 42.51, alumina 19.15, protoxide of iron 33.57, oxide 
of manganese 5.49 ( Wachtmeister). 
Precious Garnet —Silica 35.75, alumina 27.25, oxide of iron 36.00, oxide of manganese 
0.25 {Klaproth). 
Pyrenaite —Silica 43.00, alumina 16.00, lime 20.00, oxide of iron 16.00, water 4.00 
( Vauquelin ). 
Aplome —Silica 35.64, lime 29.22, oxide of iron 30.00, oxide of manganese 3.01, potash 
3.25 ( Wachtmeister). 
Grossular —Silica 40.55, alumina 20.10, lime 34.86, oxide of iron 5.00, oxide of man¬ 
ganese 0.48 {Wachtmeister). 
Manganesian Garnet —Silica 35.83, alumina 18.06, protoxide of iron 14.93, protoxide 
of manganese 30.96 {Seybert). 
Melanite —Silica 35.5, alumina 6.00, lime 32.50, oxide of iron 25.25, oxide of manga¬ 
nese 0.40 {Vauquelin). 
