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bluish channelled prisms, and has the formula (Fe,Mn)S0 4 + 7H 2 0, where 
the Mn is = about — Fe. The mineral therefore stands between mallardite 
and melanterite. It weathers, but not in the air like the one, nor becomes 
of an ochre colour like the other. The crystalline form appears to be clino- 
rhombic. It derives its name from the place where it is found. 
On the Behaviour of Silicates containing Fluorine , especially the Topaz and 
the Micas , at High Temperature. — Rammalsberg has instituted a number 
of experiments expressedly with the view of determining the form in which 
fluorine is contained in the minerals in question, topaz and the micas. He 
finds that at the high temperature of the porcelain furnace, from topaz only 
could all the fluorine be removed under favourable circumstances. His 
experiments pointed to the probability that a part of the fluorine passes off 
in the free state ; in other words, that in the presence of water vapour 
hydrogen fluoride was formed, while the elements united to the fluorine 
potassium, lithium, magnesium, iron, aluminium, silicium, remain as oxides, 
while another portion of the fluorine passes off in the form of a silico- 
fluoride. This does not support the earlier view that silicium fluoride alone 
is evolved, and supports the theory of the author that fluorine is contained 
in these silicates in the same way as oxygen is. It appears, moreover, that, 
as a secondary action of the hydrogen fluoride, not only the fluorine present 
in the topaz in the form of aluminium silico-fluoride, but a certain amount 
of silicium of the oxysilicate, is converted into SiFl 4 and evaporates. — 
( Wiedem. Ann., vii. 146.) 
New American and Australian Minerals. — Under the name of Randite 
G. A. Konig, of Philadelphia, describes a new mineral, occurring on the 
granite in the neighbourhood of Philadelphia, in crusts, of a canary yellow 
to a citron yellow hue, which are transparent and apparently crystalline. 
It has a hardness of 2*3, and when heated in a closed tube evolves water, 
and acquires an orange red colour. Before being heated it is soluble in 
cold acid; after having been heated, it dissolves completely in hot acid 
only. 0-047 gramme of material collected for analysis had the composition : — 
Lime 32*50 
Uranium oxide 31*63 
Water 6*53 
Carbonic acid [29*34] 
100*00 
The formula derived from this, Ca 5 U 2 C 6 O 20 + 3H 2 0, points to a relation 
existing between this mineral and liebigite. Before it can be determined 
whether a new species is actually present, it must be submitted to a more 
complete analysis. The name is chosen to honour Mr. Theod. Rand, of 
Philadelphia. — Stibianite is, according to E. Goldsmith, a new mineral from 
Victoria in Australia. It is massive, porous, has a reddish yellow colour, 
and a pale yellow streak, is dull, has a hardness of 5, and density of 
3*67. An analysis made by W. H. Dougherty shows it to consist of — 
Antimonic acid 81*21 
Water 4.46 
Insoluble portion 13*25 
99*22 
