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Mount Cudgewa.* 
Mount Cudgewa is about 12 miles southward from Berringama and rises 
about 3,650 feet above sea-level. The Cudgewa Creek rises here and flows 
down past Mr. Mildren’s place, and has been worked along most of its 
course for tin ore. Very rich returns are said to have been obtained along 
the bed and banks of the creek, richer than anywhere else in the State. 
The country rock is generally granitic along the course of the creek, 
and on the top of Mount Cudgewa the rock is; grano-diorite. It is in the 
grano-diorite and in the metamorphic rocks resting upon it that the tin ore . 
is met with in quartz lodes. The northern slope of the mountain near the- 
hut is thickly strewn with vein quartz, some of which has much black 
tourmaline present and in other cases silvery mica occurs in tufts; grains 
and pieces of tin ore up to an inch across are found in some of these loose 
fragments. The quartz veins have been opened up right on the ridge, and 
the vein-stone found in the shallow holes is well studded with tin ore. 
The quartz veins where opened up are from 2 inches to 4 feet in thick¬ 
ness, but most of them do not appear to be more than 1 foot thick, and 
the splashes of tin ore occur most irregularly. The lodes are in some- 
cases fairly persistent and may be traced for a few chains in length. 
They generally appear to strike more or less east and west and dip to the 
north. The veins do not All fissures but have formed by segregation from 
the mass. This is clearly demonstrated by the material tipped from the 
tunnel. Trenches and shallow holes have been dug and shafts up to 60 feet 
deep have been sunk in prospecting the lodes on the top of the ridge, and 
some good work has been accomplished in this manner. Still further to 
test the nature and value of the lodes, a tunnel has been driven from the 
south side of the ridge in a northerly direction and about 150 feet below 
the top of the ridge. This is now very hard country (granitic) 
and is 250 feet in from the mouth. Two veins of quartz carrying tin ore 
have been cut, but the distance driven is not enough to intercept the lodes 
that show most strongly at the surface, especially as they have a northerly 
dip. This tunnel should be continued for another 200 feet, and it would 
then afford an excellent means of judging whether these stanniferous lodes 
are of economic value, and if they are, the tunnel would offer facilities 
for extracting the ore cheaply. 
The lodes show best right on top of the ridge above the tunnel. The 
most easterly hole, which is about 5 feet deep, exposes a quartz lode 
4 feet thick. This is the thickest lode so far opened. One chain south of 
this is another small opening showing a quartz lode with tin ore in it. 
From the 4-ft. lode trenches and shallow holes have been made for a 
length of about 5 chains, and what is probably the same lode is' laid bare 
at intervals to- the 60-ft. shaft. The most westerly opening is north of the 
60-ft. shaft. The quartz lode in these openings would average about 
11 inches thick, and it carries a good percentage of cassiterite in crystals 
and irregular pieces. A cross-lode occurs striking W. 10 deg. N. and it 
is about vertical. The quartz is; 2 inches thick and rich in tin oxide; gold 
has been seen in this lode. This vein should pay for extraction while it 
traverses the decomposed rock, but when the hard granitic rock is reached 
it would be expensive to work such a thin lode. A shaft 16 feet deep has 
been sunk on this lode, and the stone is; as well studded with cassiterite at 
the bottom as at the surface. 
* See Professor Gregory— The Mt. Cudgewa Tin-field, Bull. Geol. Surv. Viet., No. 22. 1907. 
