Fiona,
 
A little more information on the Cornish connection with Kawau Island which was the scene of one of New Zealand's earliest commercial enterprises, a manganese and copper mining industry that thrived on the island in the mid nineteenth century. Remains of this industry are protected in the Kawau Island Historic Reserve. The Cornish engine house at Whitaker's Shaft is the most southerly example of a Cornish design engine house in the world. It has lost its bob wall, but the chimney, rear, and wing walls are largely intact.
 
Europeans first arrived on the island in the 1820s and it was purchased from the Maori in 1840 by an Aberdeen based investment company for farming. Mining on Kawau began in 1843 following the discovery of manganese at Manganese Point near North Cove. The following year copper was discovered and a mine opened by the Kawau Mining Company at South Cove which employed 20 men from Auckland and Sydney. Two years later Captain James Ninnis and a party of Cornish miners arrived to expand the operations. This operation lasted until flooding forced work to cease in 1851. 

 

Between 1844 and 1850 there were up to 300 people living on the island, many of them Cornish, living within easy walking distance of the mine. Villages were located at Two House Bay, Sunny Bay, Schoolhouse Bay, Dispute Cove, Miner's Cove and Monoma Bay (later renamed Mansion House Bay), which was the chief settlement consisting of company offices, assay house, stables and surgeon's house. The island's first school was built at Dispute Cove in 1845 and destroyed by fire soon after. In 1845 tenders were called to construct a house and offices consisting of eleven rooms at Monoma Bay for the Mine Manager, Captain James Ninnis. Parts of this original house survive and can be visited (Mansion House, where the ferry from Sandpit comes in). The building was purchased in 1862 by Sir George Grey, Governor and Premier of New Zealand, and transformed into a mansion with exotic landscaped gardens, many original elements of which remain. 

 

Some 3,000 tons of ore were extracted during the first working, making it the most profitable mining operation in New Zealand. The Kawau Mining Company had sole mining rights on the island but this was threatened when Frederick Whitaker acquired the rights to mine below the high water mark. Whitaker sank a shaft on reclaimed land at Mine Point adjacent to the existing mine and began to mine inland threatening to encroach on the sett of the Kawau Mining Company. A legal battle ensued that lasted two years and eventually the two rival companies merged.

 

Mining on Kawau presented considerable problems. The submarine workings were permanently wet through seepage or seawater flooding. Consequently, a sandstone Cornish design engine house was erected at Whitaker's Shaft at Mine Point to accommodate a 12 hp steam engine and pump reputedly imported from Cornwall (the provenance of the engine is unknown; the fact that the cylinder bedstone is missing suggests that the engine was not scrapped but sold on elsewhere). The Reverend Richard Taylor remarked on the whim, the steam engine and other buildings on the mine during a visit in 1847 (yet the interpretation boards I saw at the mine in 2005 state that the engine house dates from 1854). Problems were also encountered shipping the ore. At first this was shipped directly to Sydney where it was intended to be sent to south Wales for smelting. This was abandoned after it was discovered that the ore had the tendency to spontaneously combust, creating a hazard in wooden sailing ships. In 1849 a smelting works was therefore built at Bon Accord to partially process the ore on the island. A rival smelting operation was built on Motuketekete Island. Flooding led to closure of the mine in 1852. There were further unsuccessful attempts to reopen the mine in 1854-9 and 1900-2.
 
Some research I did over 10 years ago on Cornish migration from Lanner, a copper mining village just outside Redruth, unearthed a discrete migration network that linked Lanner, Dalton-in-Furness (an iron mining town in Cumbria) and Blackspoint (near Reefton) together in the 1860s/1870s. This network appeared to have comprised several 'core' families including the Lawns of Lanner. 
 
If you want to know more about migration networks, then I have published some stuff on this in Cornish Studies, related particularly to Latin America but applicable to other parts of the world.
 
Hope this is also helpful.
 
Regards,
Dr. Sharron P. Schwartz