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Kauri forests once covered most of the upper North Island of New Zealand; the change of climate, geological activity (volcanic activity and earthquakes) and the impact of Maori and European settlers had led to much deforestation, with some areas reverting to sand dunes, scrub or swamp, but these ancient kauri fields continued to provide a source for gum, as well as the remaining forests.[1][2] Kauri gum was formed when resin from the kauri tree leaked out through fractures or cracks in the bark, hardening with the exposure to air. Lumps commonly fell to the ground and became covered with soil and forest litter, eventually fossilising. Other lumps formed as branches forked or trees were damaged, releasing the resin.[3] The gum varied in colour depending on the condition of the original tree, where it had formed and how long it had been buried. The colours ranged from chalky-white, through red-brown to black; the most prized was a pale gold, hard and translucent.[3][4] The size of each lump also varied greatly. Swamps tended to yield the small nuggets known as "chips", whereas the hillsides tended to produce larger lumps. The majority were the size of acorns, although some were found which weighed a few pounds; the largest (and rarest) were reported to weigh half a hundredweight.[5] Kauri gum shares some characteristics with amber, another fossilised resin found in the Northern Hemisphere, but where amber can be dated as millions of year old, carbon-dating suggests that the age of most kauri gum is a few thousand years.[6]
[edit] Uses of kauri gumThe Maori had many uses for the gum, which they called "kapia". Fresh gum was used as a type of chewing-gum (older gum was softened by soaking and mixing with juice of the puwha thistle). Highly flammable, the gum was also used as a fire-starter, or bound in flax to act as a torch. Burnt and mixed with animal fat, it made a dark pigment for moko tattooing.[7] Kauri gum was used commercially in varnish, and can be considered a type of copal (the name given to resin used in such a way). Kauri gum was found to be particularly good for this, and from the mid 1840's was exported to London and America. Tentative exports had begun a few years earlier, however, for use in marine glue and as fire-kindlers;[6] gum had even made up part of an export cargo to Australia in 1814.[8] Since the kauri gum was found to mix more easily with linseed oil, at lower temperatures, than other resins, by the 1890s, 70% of all oil varnishes made in England used kauri gum.[9] It was used to a limited extent in paints during the late nineteenth century, and from 1910 was used extensively in the manufacture of linoleum. From the 1930s the market for gum dropped as synthetic alternatives were found, but there remained niche uses for the gum in jewellery and specialist high-grade varnish for violins.[9] Kauri gum was Auckland's main export in the second half of the nineteenth century, sustaining much of the early growth of the city. Between 1850 and 1950, 450,000 tons of gum was exported.[10] 1900 marked the peak in the gum market, with 10,000 tons exported that year, with a value of £600,000.[8] The average annual export was over 5,000 tons, with the average price gained £63 per ton.[11] [edit] Gumfields Kauri tree in Waipoua Forest Most of the gumfields were in Northland, Coromandel and Auckland, the site of the original kauri forests. Initially, the gum was readily accessible, commonly found lying on the ground. Captain Cook reported the presence of resinous lumps on the beach at Mercury Bay, Coromandel, in 1769, although he suspected it came from the mangroves, and missionary Samuel Marsden spoke of their presence in Northland in 1819.[4] By 1850 most of the surface-lying gum had been picked up, and men and women began digging for it. The hillsides yielded shallow-buried gum (about 1m), but in the swamps and beaches it was buried much further down (4m or below).[1] [edit] Gum merchantsGumdiggers generally sold their gum to local gumbuyers, who transported it to Auckland (generally by sea) for sale to merchants and exporters.[12] There were six major export firms in Auckland who dealt in gum, employing several hundred workers who graded and rescraped the gum for export, packing them in cases made from kauri timber.[13] As early as the 1830's and 1840's merchants, including Gilbert Mair and John Logan Campbell, were buying gum from local Maori for £5 a ton, or trading it for goods.[8] Most gum was exported to America and London (from whence it was distributed throughout Europe), although smaller amounts were sent to Australia, Hong Kong, Japan and Russia.[14] [edit] Notes
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