Traditional gold mining

Traditional gold mining

Gold is one of the earliest forms of metal found in the Philippines. The first appearance dates back to about 300 to 500 B. C. and is from the island of Palawan. Historical evidence argues that the present day Kankana-ey are part of a 800-year-old small-scale mining tradition. A Chinese record written between 1209 to 1214 indicates that the Philippines was drawn into a large gold trade network established by the Sung Dynasty. There are meticulous Spanish records regarding gold from the 1500s to 1898.

Placer Mining

Placer deposits are commonly treated by sluicing to concentrate the valuable material.

The work force in placer mining consists of family units divided into pairs, for example, a husband and wife, a mother and daughter, or a mother and son; however, mining can sometimes be done alone. In placer mining rock wall channels with floodgates called kaangs are built in the river bed. These channels can range from 25 to 59 meters in length and function as launders which are constructed from rocks dug while mining the river. Towards the end of the channel is a sluice box. A portion of the river is directed through the channel in order to carry away lighter rock and waste material. The sediment inside the channel is sifted several times through the sluice box until linang which is substantial amounts of tiny gold particles along with minute amounts of sand with pyrite, nonmetallic rock grains and metal shavings are in the sluice. At the end of each workday, the gold-bearing sand is brought home and placed in containers.

Rights to where to locate a channel are based on a first-come-first serve basis and are temporary. A channel may be worked for as long as one wants to mine it, and for as long as it is not destroyed by the heavy rains. Abandoned channels can be mined again by another as over time the river washes gold bearing sand into the channel making it again productive. Ownership is also transferable to another miner.

Processing

It is in the processing of the ore and concentrate that the Kankana-ey women are known to excel.

When large quantities of ore are processed, the miners use small mechanized, fabricated crushers. The crushed ore is loaded in rod mills or ball mills for grinding. When small quantities of ore are processed basalt and iron tools are used for grinding. After the ore is crushed in the rod mill or ball mill, women do the processing and smelting. It is not uncommon to see men process the gold ore, but even they say the women are better at processing, especially with the handling of the separator (sabak) . This figure is a flow chart of the gold recovery process.

Smelting the Gold

The Kankana-ey women use physical separation techniques to separate gold from ore. Through 1995 there was a marked contrast between traditional small-scale miners and gold rush miners. In the gold rush areas much of which is the ancestral domain of indigenous peoples, mercury is used in the recovery of gold. By contrast, the traditional small scale miners employ milling, gravitation and panning methods for gold recovery. Unlike gold-rush areas, traditional miners used painstaking measures and great care to recover gold from virtually all the solids and also recycle the water used in the process. The miners scrape the surface of the soil around the work and roasting area, collect this soil in sacks and process it for its gold content (or kidkid) ; crush and regrind the used crucible (gangi) ; and recycle the middlings and panning tails (kibo) in the holding tank (dayasan) .

There was a symbiotic relationship between Benguet Corporation while it was in operation and the Kankana-ey placer miners prior to the early 1990s. During this period the Kankana-ey sluiced the tailing’s pond of the commercial mines (saksak) ; burned and sluiced the woodchips from Benguet mill’s classifier (kuyos) ; collected ore with free gold from Benguet’s mullock area (sen-eng) , sluiced the mullock’s gold content, and sold the sand and gravel derived from sluicing to buyers from the surrounding communities and the city. Benguet Corporation also contracted the placer miners for the rocks they set aside while building their channels (kaangs) for construction of their three tailings dams and other infrastructures.

The tool complex for milling gold-bearing sand is made of small basalt rocks derived from the river. After the ore is crushed, it is milled using a tool complex of basalt grinders and mortars. The crushed ore is milled with a large lower grinder called an alintegan and an upper stone grinder called an alinteg until the ore is ground into the fine texture of what they call linang, resembling very much the gold bearing-sand mined from the river.

After milling they pan the concentrate in a galvanized iron separator (sabak) over a small holding tank (dayasan) , where the gold is separated from the unwanted materials. Some men have been observed panning with a separator, however, the women are known to be more adept at separating the gold during this procedure.

After panning the sluice concentrate is further milled with other grinding rocks. The panning concentrate is ground several times until a powder like consistency with substantial amount of gold grains is achieved.

Sometimes it is not uncommon to see the processors squeezing the juice from leaves of sunflower, tobacco, calamansi or sayote over the concentrate. This is to prevent the very fine gold from floating. After this step the panning concentrate is placed back into the separator for further panning. What remains after this procedure is almost pure gold.

Smelting the Gold

After this final step of milling the gold grains are wrapped in plastic and sprinkled with about 1/4 teaspoon of borax for flux. This is placed in an earthenware crucible and brought to a smelting area, where the crucible is placed in an open furnace and covered with charcoal.

When smelting is complete, the remaining mass is picked up with tongs and placed in a cup containing water, cooled and the slag is knocked off exposing a gold bead. This is weighed on a balance scale and sold to dealers located either within the community or the nearest city.

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