SAPPHIRE DEPOSITS NEAR THE GWYDIR HIGHWAY EAST OF GLEN INNES
Dirty Creek is in the centre of the map (from DIGS R00050764) |
When I first moved
to Glen Innes in 1988 I had with me a copy of the Records of the Geological
Survey of NSW 14(1), which contains a valuable article titled “Sapphires in the New England District, New
South Wales”. If you would like to download a copy, the DIGS reference is
R00050764. The map at the end of the document is a useful tool for locating
interesting fossicking spots. I need to point out, however, that, apart from
Yarrow Creek, some of our best sites (eg Pretty Valley, Rainy Swamp, Back Creek
and Frenchies Swamp Creek) are not indicated as sapphire bearing at all. The
map in Mineral Industry 18 Gemstones 2nd Edition (1980) DIGS
reference R00050830, is based on the earlier one.
Dirty Creek 1652 Tarcoodie 1704 (from metallogenic map) |
One place seemed to
be remote from all the others and that is Dirty Creek, near the Glen
Elgin road turnoff from the Gwydir Highway about 30km east of Glen Innes. See
the map extracts for guidance, also Google Earth. I now know that there are
gemstones to be found in many creeks in the Glen Elgin area but it isn’t an
area I’ve looked at very closely. Dirty Creek is crossed by the Glen Elgin road
immediately after the turnoff from the highway. After a few hundred metres, the
creek joins the Rocky River almost at the highway bridge. The Rocky
River is known as the Timbarra River further downstream.
Please note that
anything I say about access may no longer be true. Under no circumstances
should you enter private land without permission.
Stock reserve gate |
There is some kind of stock reserve covering the lower parts of Dirty
Creek. About 300 or so metres before the Glen Elgin turnoff there is a gate opening into
the reserve on the northern side of the highway. The creek runs through swampy
and sandy country and you wouldn’t expect to find much in it. All I ever turned
up were a few very waterworn sapphire and zircon fragments as well as black
spinel and tourmaline. These were more abundant downstream where there are
granite outcrops. Upstream you come to the boundary fence. Note that the area
shown on the Grafton-Maclean metallogenic map as being the site of mining
activity is a km or so upstream. Dirty Creek is shown as deposit number 1652
I haven’t examined Dirty Creek between the Glen Elgin bridge
and the junction with Rocky River, but there are many granite outcrops in this
stretch so there could be some gemstone concentrations waiting there for those
who don’t mind getting wet.
Rocky River reserve entrance |
Immediately after the highway bridge there is a track on the
northern side entering what appears to be another reserve, through which the
river flows. A lot of fossicking has been done here because there is usually a
good flow of water and there is a lot of gravel in the river and its banks.
I’ve only washed a casual sieve or two, but they always contained some gem
material. It’s my guess that this has come down Dirty Creek and into the Rocky
as I could find nothing upstream of the Rocky River bridge, though the usual
problems of swampy ground and access to the river make this statement difficult
to confirm.
The third gem bearing spot in the area is Tarcoodie, which I
have not been able to locate, though the mine data information suggests that
quite a bit work was done on the deposit. It is shown as deposit number 1704
and ought to be on the southern side of the road in the vicinity of the prison
farm (afforestation camp). Stay out of that area!
Extracts
from Grafton-Maclean Metallogenic Data
GR1652 (YJ0011) G
Dirty Creek OCC sapphire modern placer (fluvial)
NAME(S): Dirty Creek Recorder(s):
K. Ringwood, 24/11/1995
LOCATION Map
sheets: SH/56-6,
9338-IV-S Coordinates (MGAz56): 404206mE, 6721488mN Locality: 29
km ENE of Glen Innes
Location method: 25K topo map Co: Clive Ph:
Lewis Por: 42,
43, 45
MINING HISTORY
Workings: dredging
or sluicing Extent (m): d: l: 2000 w:
Prods and period:
Exploration:
HOST ROCK(S): clastic sediment,
alluvium, Quaternary
DEPOSIT CHARACTER
Ore minerals: (sapphire)
Alteration:
Gangue: Production:
Resources:
Ore genesis: modern placer
(fluvial) Relation to host: stratiform Orientation:
REMARKS:
REFERENCES: MacNevin
(1972), MacNevin & Holmes (1980)
GR1704 (YJ0010) G Tarcoodie deposit OCC sapphire modern placer (fluvial)
NAME(S): Tarcoodie deposit Recorder(s):
H F Henley, 7/2/1992 & 24/11/1995
LOCATION Map
sheets: SH/56-6,
9338-IV-S Coordinates (MGAz56): 409405mE, 6720368mN Locality: 36
km E of Glen Innes
Location method: 25K topo map Co: Clive Ph:
Mount Mitchell Por: 21,
22; PMA
MINING HISTORY
Workings: dredging
or sluicing Extent (m): d: l: w:
Prods and period: Gem Exploration
(July 1971 - March 1972)
Exploration: G and J Gems P/L
(1988-present)
HOST ROCK(S): felsic intrusive,
granite, Quaternary sediments, alluvial plain, Quaternary
DEPOSIT CHARACTER
Ore minerals: (sapphire)
Alteration:
Gangue: Production:
Resources:
Ore genesis: modern placer
(fluvial) Relation to host: stratiform Orientation:
REMARKS: substantial
conventional production plant type
REFERENCES: GS1990/226
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