59 
of iron with 6 equivalents, (45-9) of water, of an astringent 
taste, easily soluble in water, decomposing in the atmo¬ 
sphere, and falling down into a yellowish white powder. 
It is found in old mines at the Harz, in Saxony, near 
Schwarzenberg, etc. Sometimes it contains copper, and 
has then a remarkably fine blue colour. The sulphate of 
iron is used for black paint, in the manufacture of ink, 
sulphuric acid, etc., it is usually obtained artificially from 
vitriol-schists, or from roasted iron pyrites. Fig. 10 is an 
artificial group of crystals. 
Fig. 11—19.—Manganese Oees. 
Manganese is a blackish-grey, but friable metal, nearer 
allied to iron, very difficult of fusion, strongly resisting 
heat, only slightly magnetic, of 8'01 specific gravity, which 
loses its lustre in the atmosphere, and does not in 
nature occur native. Most frequently it is combined with 
oxygen, more rarely with sulphur, and some of these com¬ 
binations have a general resemblance to the corresponding 
iron ores, with which they are also frequently found. All 
of them, after heating with borax, give an amethyst pearl, 
and when held in the point of the flame a longer time 
with soda, a greenish-blue cloudy schlag of manganate of 
soda, which becomes colourless in the reducing flame. 
They generally possess a metallic lustre, and specific 
gravity of 3‘7—4'8. The metal manganese has as yet 
found no application in the arts, but it renders many 
kinds of iron impure without having any injurious influ¬ 
ence on them. On the other hand, the different oxides of 
manganese are used in making violet, brown, and black 
enamel colours for glass and porcelain, in the preparation 
of oxygen and chlorine, for the colouring of green glass, 
etc. 
SULPHURED OF MANGANESE. 
Is found in two combinations in nature, in the first 
place as manganese blende , or simple sulphuret of manganese, 
crystallising in cubes, iron-black, opaque, of slight metallic 
lustre, at Naygag, in Siebenburg, in Cornwall, and in 
Mexico; and secondly, as hauerite, a bi-sulphuret of 
manganese, in regular octahedrons, sometimes in combi¬ 
nation with the cube or rhombic dodecahedron, as in 
magnetic-iron, or franklinite, Plate XX., Fig. 24, also iron- 
black passing into reddish-brown, with a brownish-red 
streak, at Kalinga, not far from Altsohl in Hungary. This 
latter is amorphous with sulphur pyrites. 
Fig. 11—18.—Oxide of Manganese. 
They are all recognised by their iron-black colour and 
metallic lustre, and yield, when heated in a test-tube, 
more or less oxygen, and with hot nitric acid chlorine, 
giving more of both the greater the amount of oxygen 
contained, and therefore most can be obtained from 
pyrolusite. 
Fig. 11.—Hausmannite. 
Crystallises in quadratic octahedrons, which may be 
split perpendicularly to the principal axis, and, as in Fig. 
11, for the most part in combination with a second lower 
quadratic octahedron truncated and bevelled at the acute 
angles; compact and granular masses are also found. 
Of slight metallic lustre, and brownish black colour; the 
streak is chestnut brown, the fracture uneven, the hard¬ 
ness = 5 - 0—5‘5, and the specific gravity =4*72. Opaque, 
friable. The constituent elements are equal proportions 
of the protoxide and of the peroxide of manganese, Mn 
Mn; the composition, therefore, corresponds to those of 
magnetic iron, not so the form of the crystals however. It 
is found at Ihlefeld in the Harz, Ilmenau in Thuringia, 
Sohneeberg in Saxony, and like the other ores of man¬ 
ganese, it is principally employed in colouring enamel and 
glass. 
Figs. 12 and 13.— Braunite. 
This also crystallises in square octahedrons, which, as in 
Fig. 12, are truncated at the vertex, or, as in Fig. 13, are 
in combination with a second more acute square octa¬ 
hedron, and may be split in the direction of the octahedral 
planes. Iron-black, with brownish-black streak, opaque, 
of metallic lustre, of 6-5 hardness, and 4‘8—4’9 specific 
gravity. Infusible before the blow-pipe, and otherwise 
sharing the properties of other ores of manganese. The 
elements are peroxide of manganese Mn. It is found at 
Ilmenau in Thuringia, at Wunsiedel in Bavaria, at St. 
Marcel in Piedmont. 
Figs. 14 and 15.— Manganite. 
Crystallises in right rhombic prisms, which, however, 
are generally truncated at the acute lateral edges, as in 
Fig. 14, and exhibit marked longitudinal striation, and 
admit of cleavage in the direction of the short diagonal. 
Double truncations of the lateral edges, sometimes with 
single or double bevelling of the basal edges and basal 
angles, also occur, as in Fig. 15, and in addition, granular 
and foliated masses. It is brownish-black to iron-grey, 
opaque, of a high metallic lustre, hardness=4, and specific 
gravity = 4 , 328. It does not give off colour, and may be 
distinguished from the next ore, with which it is frequently 
confounded, principally by its greater hardness, brown 
streak, and stronger lustre. The crystals are also sometimes 
covered with the hyperoxide of manganese. In the retort it 
always gives off some water, which is an essential distinc¬ 
tion from the two foregoing ores as well as from pyro¬ 
lusite. The chemical constituents are simple hydrous 
oxide of manganese, Mn H with 10T9 of water. It is 
found principally at Ihlefeld, in the Harz, at Ilmenau, in 
Nassau, Sweden, England, etc., and is generally met with 
in commerce, mixed up with pyrolusite, under the name 
of grey manganese ore . It yields very little chlorine and 
oxygen. 
Figs. 16 and 17.— Pyrolusite, Grey Ore of Manganese. 
Crystallises likewise in right rhombic prisms of 86° 20' 
and 93° 40", which, however, like Fig. 16, are mostly 
