74 CATALOGUE OF MINERALS ; 
A limestone from the Potosi claim, Irvinebank, Tinaroo district, 
which, with hematite from the same claim, is raised to flux silver- 
bearing lead ores by the Silver Valley Smelting Company has 
been analyzed by the same gentleman with the following result :— 
Moisture - : - - : 1.07 per cent. 
Carbonate of lime . : 2 | 'O5:630 aes 
Silicaaae ; . ‘ : ‘ 2:4 asus 
Peroxide of iron . : : : O78. 4; 
Carbonate of magnesia . : : O;4 7. ies 
100.56 
A limestone from Northumberland Island, Broadsound, is said 
to give by analysis :— 
Carbonate of lime . , : 5 98 per cent. 
Foreign matter : i : 5 Di ae 
100 
This stone is burned for the manufacture of lime, as well as 
used for building purposes. 
A marble of white colour which takes a fairly good polish is 
obtained from Warwick, also as well as some of darker shades ; the 
white and coloured marbles of Gladstone are very fair ornamental 
stones. Marble is also obtained from Reid’s Gap, near Towns- 
ville (an impure saccharine marble), from Herberton, and from 
Rockhampton. 
MAGNESITE—Comp. carbonate of magnesia Mg C O,. 
Magnesite occurs on the Main Range, near ‘Toowoomba, and in 
the serpentinous district near Rockhampton. A magnesite from 
Islaport, Rockhampton, gave Mr. Clarke on analysis :- - 
Silica. ‘ ‘ : : : 7.23 per cent. 
Carbonic acid : ; - - 410s as 
Peroxide of iron . f : é 1.60 = ee 
Magnesia : : ‘ - « ~' 'AG:7018 Bae 
Line : : : 3 . traces 
101.67 
CHALYBITE—SIDERITE—Compp Fe, C O,. 
A very siliceous carbonate of iron was passed through in sinking 
a well on the Ejight-mile Plains, near Brisbane, Sphcerosiderite 
(concretionary chalybite) has been noticed in basalt near Too- 
woomba. Chalybite also occurs with hematite and with calcspar 
containing gold in Uncle Tom’s reef, near Cloncurry. 
