BY EDWD. B. LINDON, A.R.S.M. WS 
WITHERITE—Comp. Ba C QO, . 
The occurrence of witherite at Springsure has been noticed. 
CrERuUsSSITE—Comp. Pb C Og. 
This mineral, essentially a decomposition product from galena, 
is met with on almost all galena lodes. In the Star River 
(Argentine) Silverfield a cerrussite assays 69 per cent. of lead and 
186 ozs. of silver to the ton. At Mount Garnet, near Herberton, 
decomposing galena is stained with green carbonate of copper and 
contains crystals of cerussite. Litharge and cerrussite are derived 
from the galenas of Newelltown in. the same locality. Cerussite 
from Ravenswood assays 150 ozs. of silver to the ton. 
SMITHSONITE—Comp. Zn C QO, . 
I have had sent to me a specimen of this mineral from a 
locality near Bowen. 
MALACHITE—Comp. 
Green carbonate of copper is found staining quartz and other 
rocks in very many places, owing to the decomposition of copper 
pyrites, which is so widely-spread a mineral ; moreover as malachite 
is rather a showy mineral, and very small quantities of copper 
pyrites give rise to a good deal—comparatively—of carbonate, the 
prospector if unmindful of this is liable to be much mistaken as 
the value of his find. From the same cause—decomposition- — 
malachite is frequent in “gossans” or ‘‘caps” of lodes, as at 
Mount Garnet, Tinaroo district, and in the Rainbow lode, Duck 
Creek, near Cloncurry. 
In the Peak Downs copper mines malachite was found in very 
fine massive blocks of botryoidal structure, and also in small 
crystals and in fine silky needles. 
At the Mount Orange copper mines malachite occurs with 
specular iron ore, with azurite and hematite, and with black oxide 
of copper. 
At the Mount Perry copper mines malachite and azurite occur, 
but not in very large quantities in comparison with some other 
districts. 
Malachite and black oxide of copper occur in the Buck claim, 
Ravenswood, their presence being determined by the decomposi- 
tion of the auriferous chalcopyrites which accompanies sphaelerite, 
