BY W. F. PETTERD. 37 
It occurs in coralloidal aggregations and mammillary patches 
implanted upon Limonite and Psilomelane. 
Central Dundas and other mines, Dundas. 
105. HYPERSTHENE (Silicate of Magnesia, Calcium, and 
Iron). 
On the east side of the Parson’s Hood Mountain. This 
mineral occurs with Schiller Spar and Dialage Rock ; occasionally 
it contains specks of Copper Pyrites. 
Fairly abundant at the Heazlewood; on the Forth River ; 
Meredith Range ; Dundas. 
106. HYDROMAGNESITE (Hydro-carbonate of Magnesia). 
An amorphous mineral resulting from the alteration of Brucite. 
It has not been found in a crystallized condition, its usual mode of 
occurrence being in the form of chalk-like crusts. In Serpentine 
with Brucite. 
Heemskirk ; (Ballarat School of Mines, Museum) ; ofapparently 
rare occurrence in thin incrustations, Heazlewood. 
107. HORNBLENDE (Silicate of Lime, Magnesia, Iron, c). 
Occurs massive, forming a large lenticular rock inass at Mount 
Ramsay. The rock is fine to fairly coarse subcrystalline structure 
of a black colour with a dull lustre. It in many respects resembles 
an analogous formation at Biggenden, Queensland; there is also 
a strong resemblance as regards the associated minerals, both con- 
taining the metal Bismuth, Pyrites of various kinds, and Gold. 
In the Biggenden mine the metallic minerals occur of a more 
oxidised or secondary character than at Mount Ramsay, but both 
have many striking points of resemblance to each other. The 
same variety of rock is also abundant at the Hampshire Hills, but 
without many of the minerals common to the Queensland locality 
and Mount Ramsay; columnar Hornblende occurs at a locality 
about six miles east of the Hampshire Hills and west of the 
Blythe River; it is found in combination with a large deposit of 
Maenetic Iron ore. The blades of this mineral, if they occurred 
without cleavage planes, could be obtained up to nearly two 
feet in length. The colour of the mineral is a very dark green to 
almost black; to the south-east of the Hampshire Hills a peculiar 
fibrous brown variety occurs. It is found in masses having much 
the appearance and structure of Chrokidolite from South Africa : 
examples have been broken out measuring above one foot in length. 
At the Heazlewood an extensive mass occurs which is many feet 
in thickness ; it occurs as aciculated crystals which are interlaced, 
forming an almost solid compact rock of a pale asparagus-green 
colour, On the western side of the Heazlewood River a dark grey 
coloured form has been found in considerable quantity. 
Abundant near the Madam Melba mine, North Dundas ; at the 
