Additional exploration has increased the size of the iodine resource at the Aguas Blancas property, reports owner
The Aguas Blancas project comprises 22,000 ha in northern Chile’s Atacama Desert, 95 km southeast of the port of Antofagasta.
Atacama plans to mine and process caliche ore on-site. Caliche ore contains high concentrations of the evaporite minerals sodium sulphate, sodium iodide and sodium nitrate. The processed minerals are used in commercial-grade iodine, detergent-grade sodium sulphate and fertilizer-grade potassium nitrate.
Atacama began in April a detailed evaluation of mineralization at the Repasos deposit, just west of the Aguas Blancas deposit. The Repasos deposit is said to be higher in iodine and lower in sulphates than the other reserves at Aguas Blancas.
The company performed extensive trenching and bulk sampling. Assays from 103 of the 114 trenches indicate that the average grade of the resource is 10.8 million tonnes averaging 619 parts per million (ppm) iodine, 8.38% chloride, 17.68% sulphate, 4.8% nitrate and 52.69% insolubles. The cut-off was 300 ppm
Atacama expects the Repasos resource to sustain a production rate of 1,000 tonnes of iodine ore per year for the first few years of the heap-leach operation. Thereafter, the main Aguas Blancas deposit, containing proven and probable reserves of 33 million tonnes averaging 552 ppm iodine, 22.63% sodium sulphate and 2.64% nitrate, will be processed through heap leaching or conventional milling.
Data from two small heap-leach pads will be used in the construction of processing facilities, and to confirm recovery rates and costs. One pad is testing Repasos material, the other, original Aguas Blancas reserve material.
The Repasos pad is processing a 1,300-tonne bulk-sample. After 31 days of operation, iodine recovery stands at 67%. Low chloride and sulphate content makes the Repasos ore amenable to heap leaching.
The pad containing a similar amount of Aguas Blanca ore is in the early phases of leaching.
Construction of a low-cost, 1,000-tonne-per-year iodine heap-leach facility is scheduled to begin by the third quarter of 1999. Future plans call for a production expansion to 300,000 tonnes of sodium sulphate and 70,000 tonnes of potassium nitrate per year.
At the end of the first quarter, Atacama reported a cash position of about $6.4 million.
Be the first to comment on "Atacama boosts iodine resource"