Hedleys Water Race
In 1865 the McIvor Hydraulic and Gold Mining Co began constructing a water race from the headwaters of the McIvor Creek near Mt. Sugarloaf at Tooborac, to convey water at a sufficient elevation to command the whole McIvor gold field. The race was anticipated to carry six million gallons per day to operate 60 sluice heads.
The water was conducted to the sluicing site in an open channel which followed the contour of the ground to a well constructed flume, made of three sawn planks about 12 inches wide and one inch thick. Then it went into a heavy canvas hose, to increase the pressure and at the end of the hose there was a nozzle made of stout galvanised iron tipped with cast iron.
Initially only seven miles (about 11km) was to be constructed. This required tunneling for short distances, construction of flumes or aqueducts across gullies as well as the formation of the race walls.
The engineering feat of creating the fall of the water along the length of the race was measured using a beer bottle containing waater a a level.
In 1874 Thomas Hedley continued the water race to bring water to a holding dam he constructed in Long Gully (known as Hedley's Dam} and on to Red Hill, a distance of 26 Miles (about 42km).
In 1887 Hedley and the Hon JA Wallace began experimenting with Hydraulic sluicing by pumping, instead of relying on the pressure gained from the gravity fed water race.
In 1886 sludge in the creek became a significant problem and The Sludge Inquiry Board was formed. In 1890 the Heathcote Sluicing Company's mining lease was not renewed due mainly to the decisions made by The Sludge Inquiry Board.
Granite Basics
Three things distinguish granite.
First, granite is made of large mineral grains (its name is Latin for "granum," or "grain") that fit tightly together. It is phaneritic, meaning its individual grains are large enough to distinguish with the human eye.
Second, granite always consists of the minerals quartz and feldspar, with or without a wide variety of other minerals (accessory minerals). The quartz and feldspar generally give granite a light color, ranging from pinkish to white. That light background color is punctuated by the darker accessory minerals. Thus, classic granite has a "salt-and-pepper" look. The most common accessory minerals are the black mica biotite and the black amphibole hornblende
Third, almost all granite is igneous (it solidified frommagma) and plutonic (it did so in a large, deeply buried body or pluton). The random arrangement of grains in granite—its lack of fabric—is evidence of its plutonic origin. Other igneous, plutonic rocks, like granodiorite, monzonite, tonalite and quartz diorite, have similar appearances.
Pink Cliffs
Prior to the discovery of gold this area was open box forest growing on red-brown soil over a layer of gravel. The first nuggets of gold were found in 1852 and sluicing began using the creek water to wash the gold laden soil.
The colour Kaleidoscope you can see today is the remaining granite sliced through with reddish brown cracks filled with quartz. the surface fine granite was washed by percolating ground water containing sodium, chlorides and carbonates, which helped to dissolve the iron ore minerals and weather the granite.
In the process, the granite became stained with iron rich solutions, the colour intensity being directly related to the amounts of iron ore minerals within the cracks. Erosion has proceeded at such a rate that the present surface still resembles a moonscape
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At the listed co-ordinates if you look down at the ground at your feet you will see various colours, what are the 4 main colours of the ground and stones.
Now head back down the track and go to the Upper viewing area (WP2) at S 36° 55.903 E 144° 42.275
3. When you look across from the viewing platform under the tree line how many distinct colour layers do you see?
4. What predominant colour is the moonscape?
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Sources:-
http://geology.about.com/od/more_igrocks/a/granite.htm