Extracting gold from the fields at Waipori started simply, but over time more and more expensive and sophisticated methods were used to get hold of the precious yellow metal. Many different gold-mining methods used in New Zealand were employed at Waipori, and some pioneering dredging techniques were used here for the first time.
Alluvial mining
In alluvial mining, prospectors sorted through sand, earth and rocks left by rivers in a flood plain (which is called ‘alluvium’) to find small fragments — or hopefully larger nuggets — of gold. It’s a separation process and doesn’t involve any physical or chemical processing of the rock, and relies mainly on gold being much heavier than the alluvium.
The gold rush at Waipori began with individual gold diggers using hand tools — just a shovel and gold pan — to recover the gold. Soon they started buying timber, which was scarce and expensive in the area, to build sluice boxes and cradles for more efficient alluvial mining.
Once the most easily-accessible gold had been recovered the miners had to turn to more organised and sophisticated techniques to extract the precious metal. This usually involved them banding together to form teams (‘parties’) or companies, and raising capital for development of things such as water races to power sluices and digging down to reach gold beneath the surface.
Increasing amounts of water were needed to wash for gold and water races were built, ranging from a few hundred metres long to one more than 30 km in length. Tailraces were built to remove the washed material once the gold was extracted, usually dumping the debris into the Waipori River.
Quartz mining
It’s all very well picking out gold that had been washed down rivers, but where was the gold coming from? Finding the sources was the next quest, and once the sources were found new methods would have to be used to extract the gold from the mother lode of quartz rock.
Quartz mining started as early as 1862, in which gold-bearing rock was mined and crushed in batteries so the gold could be extracted physically or chemically.
The first quartz mining at Waipori — and the first anywhere in Otago — was done by a party of six miners from the Shetland Islands, off the north coast of Scotland, so the business was known as the Shetland Quartz Reef Company. Eventually mining on this quartz reef was taken over by the Otago Pioneer Quartz Mining and Crushing Company, known as the OPQ. This company had several different owners during its life, and erected different batteries at several different sites. The last battery stopped work in 1902 and the plant was dismantled and sold.
More than 70 quartz mining enterprises were begun at Waipori over the time the gold fields were active.
The most well-known apart from the OPQ was the Canton reef, discovered by a group of Chinese miners in 1877. The Canton mine was operated intermittently by different owners until about 1912, and you can read more about this business here.
Dredging
In the late 1880s some miners turned their attention to a different way of extracting gold — dredging. The first dredge was launched in 1890 and others followed.
Fuel was a major expense and the dredge companies experimented with different fuels to lower operating costs. Coal and coal dust were brought all the way from Westport on the West Coast and from Kaitangata near Balclutha. Cartage was forever a high cost with wagons laden with coal continually traveling between the railhead at Lawrence and the dredges that were spread up and down the Waipori River. Some dredges burnt large quantities of manuka from the Waipori Bush, and some used water (hydraulic) power.
Dredging brought new life and new people to Waipori. The population that was starting to dwindle increased as engineers and dredge masters arrived in the district. Local men became dredge hands and wives ran boarding houses for the growing population. Local businesses thrived.
In total about 17 dredges operated on the Waipori River, but they didn’t last long. Many went out of business in the first decade of the 1900s, and the final one fell silent in about 1914.