The plant specialised in smelting low grade ores and other feedstocks, particularly Bolivian tin ore, and the recycling of flue dust, processing materials other facilities or countries were unable or had refused to process.
22.
Production of asbestos, chrome, coal and nickel increased, while the improvement in gold output was attributed partly to new computerized technology enabling low grade ore deposits to be economically exploited for the first time.
23.
Following the end of World War I, in 1918 the Bwana Mkubwa Copper Mining Company embarked on a massive programme of investigating the possibility of extracting copper from low grade ores using a flotation process.
24.
The steep, wet, timber-covered, seaside mountain setting provided water power, transportation, and lumber such that, " extraordinarily low costs of operation make available low grade ore that under conditions only slightly different would be valueless ."
25.
In January 2009 it was announced that the Sandstone operation, which was to close in February that year, would remain active because of higher gold prices, which made processing low grade ore from " Lord Nelson " more profitable.
26.
In 1919, following relaxation of wartime controls by the British Metal Corporation, the copper price plunged from about ?10 per ton at the start of the year to ?5 per ton in April, dashing the company's optimism regarding treatment of low grade ores.
27.
Both young men were fascinated with airplanes and opened Denver's first commercial airport in 1918 at 26th Avenue and Oneida Street in North Spiral Concentrator, which was used extensively in the mining industry for the separation of minerals and heavy metals in low grade ores.
28.
The Guggenheims also had a process for treating the low grade ores developed by Elias Anton Cappelen Smith and were immediately interested, organised the Chile Exploration Company ( Chilex ) in January 1912 and eventually bought out Burrage for US $ 25 million in Chilex stock.
29.
This was from the 700 foot level of the old north mine, and dumped directly into the cars, the railroad passing within a few feet of the shaft . It is low grade ore, assaying $ 26 or $ 28 to the ton, and will yield under the stamps not far from $ 17 per ton.
