The West Coast of Nelson Province was neglected and scarcely known for almost 20 years after the settlement of Tasman Bay. It first excited curiosity late in 1859 when small samples of alluvial gold were discovered in the Buller Gorge by a survey party under J. Rochfort. Vigorous exploratory activity followed in 1860 when provincial government parties were sent to find routeways, map the Buller coalfield, report on timber and mineral resources, and examine potential sites for settlement. A few miners from Golden Bay came by sea to the Buller in 1861 and won small quantities of gold from the river beaches, while in 1863 the open country in the central Grey Valley was taken up in three pastoral runs. The main inrush of the mining population took place in the extreme south of the province in July 1865 when diggers crossed from what were then the west Canterbury goldfields, spread up the Grey Valley and its numerous tributary creeks, and within 12 months were prospecting in the Inangahua Valley. In the spring of 1866 a large rush occurred to the terraces and beaches of the Buller coast plain. Three bustling mining camps, Charleston, Brighton, and Addisons, each of more than 1,000 people, sprang up within a few months. Charleston, with 1,800 people at the 1867 census, was then the second largest urban centre in Nelson Province. Until 1870 only alluvial gold had been worked on the West Coast but in that year gold-bearing quartz lodes were discovered in the hills east of Reefton and at Lyell. A steady flow of population set in to the Reefton district from the declining alluvial diggings and, despite great difficulties presented by the terrain and bush cover, machinery was established on the lodes by 1873. Quartz mining was a more stable basis for settlement than alluvial gold working. The most productive years at Reefton came in the decade after 1900 and new lodes were discovered in the district as late as 1920.
In Nelson, as in Canterbury, the special administrative needs of new mining districts remote from the provincial capital were met, between 1865 and 1868, by granting wide discretionary powers in local government to a nominated official. Nelson was fortunate in its choice of T. A. Sneyd Kynnersley as commissioner of the south-west goldfields. A young former naval officer, Kynnersley displayed remarkable skill and energy in dealing with a roving community of high spirited and independent gold diggers. His popularity, together with the provincial government's willingness to spend money on public works on the goldfields, were probably the main reasons why the Nelson south-west goldfields remained harmoniously attached to the parent province when Westland was agitating for separation from Canterbury.
Nelson Province did not share to any great extent in the colonial public works and immigration developments of the 1870s. Some 1,800 assisted immigrants came to the province, including several hundred to a government-sponsored farm settlement at Karamea on the West Coast. The gold rushes, however, had drawn attention to the bituminous coal resources of the Buller and Greymouth coalfields; the first spasmodic mining had been to supply fuel for steamers in the goldfields trade. A major expansion of coal mining came in the 1880s, the capital being subscribed largely in Dunedin. Within the Buller district a regrouping of population occurred as gold-mining townships on the coastal plain decayed and new coal-mining settlements were established on the high and rainswept plateau north of Westport. The labour force for coal mining was supplied not so much from the ranks of the gold diggers as by direct immigration, over a long period, of family groups from the coalfields of Great Britain.