This historic place was registered under the Historic Places Act The Victoria Battery complex at Waikino was built in , to process ore being produced at the Martha, Waihi and Grand Junction mines. The MacArthur-Forrest cyanide process for the extraction of gold and silver from crushed ores was developed in Scotland in The patent was owned by the Cassel Gold Extraction Company.
This money had been recouped by from the small royalty charged to the users. The local invention in of the Brown or B and M agitator tanks known in some countries as Pachuca tanks , facilitated this increase in the extraction rate. The process involved cylindrical tanks in which the mix of pulverised ore and cyanide solution was agitated by charges of compressed air forced through the inverted conical bases.
This air also provided a supply of - oxygen which further improved the extraction of the metals. The tanks which were built at the Victoria Battery between and , were steel cylinders 4. Elsewhere tanks were made of wood or concrete.
A spectacular set of concrete tanks survives at the Union Hill, Waihi. The cyanide tank holders at the Victoria Battery site, Waikino, are a visible reminder of the successful field application of an improved method of extracting gold and silver from crushed ores.
The method had been discovered in Scotland, but its industrial application was a local development. The holders and adjacent ruins indicate the large scale of the gold mining enterprise at Waihi and Karangahake. These cyanide tank holders make full use of the plastic qualities of poured concrete in the form of interlocking hexagonal elements.
