Ultra Resources Inc. is happy to report that it has received the final results of metallurgical testwork performed on the bulk sample from its fully owned Chepes Gold Project located in La Rioja Province, Argentina.
Yantai Xinhai Mining Research & Design Co., Ltd., Shandong, China (Xinhai) was contracted to perform the test work. The final results revealed an overall recovery of 94.34% gold through a combination of copper masking, gravity separation, and leaching using the CNLITE reagent.
The bulk sample contained two samples with an overall weight of 849 kg obtained from the Al Espinillo and Callanas mining licenses.
Metallurgical Testwork Highlights
- The aim of the test work was to target the gold recovery from the mineralized rock which is currently in an oxidized state. Preliminary head sample assay indicates an average 13.41 g per ton (g/t) gold (Au), 32.15 g/t silver (Ag), 0.96% Zinc (Zn), 2.78% lead (Pb), and 0.47% copper (Cu).
- The latest test results indicate that concentrates can be obtained by crushing the mineralized rock to -200 mesh, yielding 33% with a gold grade of 1,530 g/t. Gravity separation yielded an overall gold of 38.19%. The gravity tailings with a gold grade of 8.20 g/t were collected as a feeding material in the subsequent tests.
- Gravity tailings were subjected to a pre-leaching process by introducing a masking agent, and then treated through the leaching process with CNLITE serving as the leaching agent and lime acting as a protective alkali. This method resulted in a gold leaching rate of 90.85% under a leaching time of 24 hours, and 91.95% under a leaching time of 48 hours. Leaching along with gravity concentration can produce an overall recovery rate of 94.34% (38.19%+61.81%*90.85%) and 94.41% (38.19%+61.81%*91.95%) under a leaching time of 24 hours and 48 hours, in that order.
- According to Xinhai, CNLITE is the latest eco-friendly gold leaching reagent developed by the Xinhai Group. Some countries are currently using CNLITE as an alternative to standard cyanide as a gold extraction agent. While cyanide is an extremely toxic reagent, CNLITE has several benefits like high leaching rate, environmentally friendly, extremely cost-effective, and rapid recycling. Moreover, the use of CNLITE does not alter the existing gold extraction equipment and cyanidation process.
We are very pleased with the outcome of metallurgical testwork which is an efficient and cost-effective process due to the use of CNLITE instead of traditional cyanidation. Its nontoxic and environmentally friendly features will be helpful in permitting and community approval. The Company’s goal is to continue exploration on its projects to create new jobs for the community and install a gold extraction plant as soon as possible to start processing mine dump material available at the Callanas and Al Espinillo mines.
Dr Weiguo Lang, CEO, Ultra Resources, Inc.
About Yantai Xinhai Mining Research & Design Co
Shandong Xinhai Mining Technology & Inc. is a stockholding high and new technology company that offers “Turnkey Solution for Mineral Processing Plant” such as research and design, equipment procurement, machine manufacturing, mine operation, management service, procurement and management of mine materials, and also industry resources integration.
Xinhai has mining technologies and a total of 500 mine EPC projects, in addition to an experience of 112 patents and 70 kinds of ores. To date, the company has established overseas offices with products exported to over 90 nations.
About La Rioja Gold Project
Located in the south of the province of La Rioja Argentina, the gold project contains three exploration and prospecting regions and 13 manifestations of discoveries (mining licenses). The area also contains many historical gold mines as well as quartz veins in granodiorite rocks hosted by previous Paleozoic shearing.
Gold mineralization is often linked to epithermal style shear hosted quartz veins. Preliminary assessment of dump material available for historical mines on the Property shows that about 25,000 to 30,000 tons of dump material is available for processing various metals, including gold.