324 A, LIVERSIDGE. 
Tron sesquioxide, Fe, wy ie aes mis? 
Manganese oxide, nO ins 25 
Tungstic acid, Wo, ‘a net “oe 06 
98°58 
Another specimen from the same locality, but water worn, was 
found to be harder = 7, with a sp. gr. of 6°54. The powder of 
this was brown. 
. Analysis. 
Tin oxide, SnO, ..... soe oe sii ee 
Silica, SiO, i 
Oxide of manganese, “Mn0.. ‘98 
Tron sesquioxide, Fe,O, ... cn a0 oS 
Tungstic acid, WO,. ve an a 36 
98°75 
The loss of 1-25 on this, and 1-42 on the previous specimen, 
may indicate the presence of some of the rarer elements not 
specially sought for, and that the specimens are worthy of further 
examination. 
Topaz—Shoalhaven District. 
In the form of short columnar prisms, the terminal pyramidal 
planes not well developed, seated on granite. Of a greyish tint, 
more or less opaque, but translucent in parts. 
Most of the crystals were about 4” to 3” in diameter, and about 
3” long, closely packed together so as to form a solid layer of 
topaz next to the supporting rock. The crystals are brittle, some 
of the faces are slightly rough, as if etched. Hardness, 7°5 only. 
Sp. gr. 3°56. 
Before the blowpipe it decrepitates, darkens, but become — 
nearly colourless again on cooling. Gives off a little water when 
heated in tube. 
a Analysis. 
Silica ee a ea ee is 
Alumina... 6% yes Si ... 62°66 
Fluori 1401 
uorine... oes es a 
Water at 100° eve evi os vice cee 
