218 NEW SOUTH WALES MINERALS. 
HornsiENDIC MINERAL. 
A light grey, sub-translucent mineral, which breaks in places 
something like a very fine-grained quartzite or jade, with somewhat 
conchoidal surface ; in other places there is a fibrous structure due 
to the presence of bright acicular crystals. The weathered por- 
tions are stained brown with oxide of iron, and show the cavities 
left by fossils. It seems to have been highly charged with the 
shells of spirifera. 
Collected by Mr. C. 8. Wilkinson, F.G.8., on the MudgeeRoad. 
Partly soluble in acid. 
Extremely tough. Hardness 6-7. Sp. gr. 3-003. 
Analysis. 
Loss on ignition ... $e si "60 
Silica ie wey as 50°44 
— “it 619 
ron sesquioxide ... 125 
i Si ets gos a rate sie 28°70 
Magnesia ... se iis ae ss 11°14 
Soda eve ia ive wee ae 1°16 
100° 
LIMESTONE. of 
Slightly crystalline, of a grey colour, with a few thin strea ie 
a lighter colour. Small patches of a pale green mineral can 
de in parts, something like glauconite in appearance. notice- 
tains a considerable amount of impurity, and leaves ’ 
able residue when decomposed with hydrochloric acid. 
