362 Scientific Intelligence Mineralogy. 
remarkable minerals which are found in the limestone mourn, 
tains of the parish of Pargas, in the neighbourhood of Abo, 
there is one of a radiated structure and white colour, which has 
been taken for a tremolite, but which should be referred to the 
Tafelspath of the Germans. According to the examination which 
M. BonsdorfF has made of it, in 100 parts it contains, 
Silica, 52.58 
Lime, 44.45 
Magnesia, 0.68 
Oxide of Iron, 1.13 
Volatile parts, 0.99 
99.93 
This mineral is therefore a bisilicate of lime, and has for its 
representative formula CS 2 . — Bonsdorff, Mem. Acad. Petersb. 
1825. 
16. Notice regarding Steatite or Soap-Stone , and its princi- 
pal uses . — Steatite is, as is well known, a variety of the talc 
genus. Its colour is white, green, or grey ; it is also sometimes, 
though rarely, red and yellow. Its specific gravity varies from 
2.60 to 2.66. It is a compound of silica, alumina, magnesia, 
oxide of iron and water, which vary according to the locality. 
It is very common in Cornwall and Germany. As it is fusible 
only at an exceedingly high temperature, and is easily wrought, 
excellent crucibles may be made of it, which are further harden- 
ed by fire, and which are only with great difficulty penetrated 
by litharge. It is also employed in making moulds for melting 
metals. In England it is used in the manufacture of porcelain. 
M. Vilcot, an artist of Liege, made several trials of it with the 
view of finding out whether it might not be susceptible of being 
employed by the lapidaries. He prepared cameos of this sub- 
stance, the colour of which he brightened in the fire, and which 
he rendered so hard by the elevation of the temperature, as to 
give sparks with steel. They were then coloured, yellow, grey, 
or milk-white, by different solutions. He polished them upon 
the stone, and ended with making them assume all the lustre of 
agate. Some pieces even resembled onyx in colour ; but a se- 
rious inconvenience was, that the markings were easily altered 
by the fire, and could no longer be restored. Steatite has a great 
affinity for glass ; it is also employed, in the manner of paste, re- 
duced to a fine powder, and mixed with colouring matters, 
for painting upon this substance* It also serves as a sympathetic 
