Effect of roasting on fine gold recovery from refractory ores

The study examines leaching of gold from refractory ore (carbonaceous metasomatites in diorite) from the Delken gold deposit. The analytical tests showed the presence of native iron, copper, carbonaceous material and gold in very fine forms (up to 2 microns). Five leaching methods were tested on three particle size fractions: –0.2+0.074, –0.074+0.04 and –0.04+0.0 mm. The solutions tested were: cyanide, ammonia-cyanide, flotent GL3G, thiourea, and sodium thiosulfate. The tests were carried out both with and without pre-roasting. The test results proved high efficiency of pre-leaching roasting for refractory ore (carbonaceous metasomatites in diorite). The results showed that roasting significantly improved gold extraction, increasing recovery by an average of 31%, and up to 56% in some cases. The best results were achieved with the pre-roasted samples –0.2+0.074 mm in size and with the use of flotent G350 (79.7% recovery) and thiourea + H2SO4 (72.6%). Thiourea leaching proved to be a promising and more eco-friendly alternative to cyanide, making it worth further study with a view to selecting the most efficient parameters for this technological process. 

Konstantinova A. V., Konareva T. G., Lavrik N. A. Effect of roasting on fine gold recovery from refractory ores. MIAB. Mining Inf. Anal. Bull. 2026;(2):128-141. [In Russ]. DOI: 10.25018/0236_1493_2026_2_0_128.

The study was carried out using the resources of the Shared Use Center for Research of Mineral Raw Materials at the Khabarovsk Federal Research Center, Far Eastern Branch RAS, supported by the Ministry of Science and Higher Education of the Russian Federation under Contract No. 075-15-2025-621. 

A.V. Konstantinova¹, Junior Researcher, e-mail: alexalavrikxx@gmail.com, ORCID ID: 0000-0002-8406-1016,
T.G. Konareva¹, Graduate Student, Researcher, e-mail: konar_tat@mail.ru, ORCID ID: 0000-0001-9889-3721,
N.A. Lavrik¹, Senior Researcher, e-mail: lavrik@igd.khv.ru, ORCID ID: 0000-0002-0808-6115,
¹ Mining Institute of the Far Eastern Branch of the Russian Academy of Sciences, 680000, Khabarovsk, Russia.

A.V. Konstantinova, e-mail: alexalavrikxx@gmail.com.

1. Mayorova T. P., Efanova L. I. Typomorphic features of native gold from gold-arsenic-sulfide occurrences in the Manitanyrd region (Polar Urals): comparison with similar types of gold mineralization in northeastern Russia. Geologiya i mineral'no-syr'evye resursy Severo-Vostoka Rossii 2024. Materialy XIV Mezhdunarodnoy nauchno-prakticheskoy konferentsii [Geology and mineral resources of the North-East of Russia 2024: Proceedings of the XIV International scientific and practical conference dedicated to the 300th anniversary of the Russian Academy of Sciences and the 100th anniversary of the gold mining industry of the Republic of Sakha (Yakutia)], Yakutsk–Novosibirsk, 2024, pp. 150—154. [In Russ]. DOI: 10.53954/9785604990100_150.

2. Savva N. E., Kravtsova R. G., Anisimova G. S., Palyanova G. A. Typomorphism of native gold (geological-industrial types of gold deposits in the North-East of Russia). Minerals. 2022, vol. 12, no. 5, article 561. DOI: 10.3390/min12050561.

3. Volkov A. V., Savva N. E., Sidorov A. A., Prokofiev V. Y., Goryachev N. A., Voznesensky S. D., Al’shevsky A. V., Chernova A. D. The Shkolnoe gold deposit in the North-East of Russia. Geology of Ore Deposits. 2011, vol. 53, no. 1, pp. 1—26.

4. Khasanov I., Mikhalitsyna T., Makarova D. Geological and geophysical characteristics of dike-type gold mineralization (using the Shakhtnoye deposit as an example). Geologiya i mineral'no-syr'evye resursy Severo-Vostoka Rossii 2024: Materialy XIV Mezhdunarodnoy nauchno-prakticheskoy konferentsii [Geology and mineral resources of the North-East of Russia 2024: Proceedings of the XIV International scientific and practical conference dedicated to the 300th anniversary of the Russian Academy of Sciences and the 100th anniversary of the gold mining industry of the Republic of Sakha (Yakutia)], Yakutsk–Novosibirsk, 2024, pp. 258—262. [In Russ]. DOI: 10.53954/9785604990100_258.

5. Fazlullin M. I. Kuchnoe vyshchelachivanie blagorodnykh metallov [Heap leaching of noble metals], Moscow, 2001, 647 p.

6. Habashi F. Principles of extractive metallurgy: Pyrometallurgy, 1st ed. Routledge, 1986, 494 p. DOI: 10.1201/9780203742112.

7. Ng W. S., Liu Y., Wang Q., Chen M. The fate of the arsenic species in the pressure oxidation of refractory gold ores: Practical and modelling aspects. Mineral Processing and Extractive Metallurgy Review. 2023, vol. 44, no. 1, pp. 1—33. DOI: 10.1080/08827508.2022.2030326.

8. Hong Qin, Xueyi Guo, Qinghua Tian, Dawei Yu, Lei Zhang Recovery of gold from sulfide refractory gold ore: Oxidation roasting pretreatment and gold extraction. Minerals Engineering. 2021, vol. 164, article 106822. DOI: 10.1016/j.mineng.2021.106822.

9. Meng Y., Wu M. Pretreatment process on refractory gold ores with arsenic. Journal of Minerals & Materials Processing. 2020, vol. 45, pp. 112—118.

10. Marsden J., House C. The chemistry of gold extraction, 2nd ed. Society for Mining, Metallurgy, and Exploration, 2006, pp. 451—473. DOI: 10.1007/BF03215543.

11. Dunn J. G., Hewitt D. Improving gold recovery through modern roasting practices in refractory ores. Minerals Engineering. 2020, vol. 148, article 106215. DOI: 10.1016/j.hydromet.2019.02.008.

12. Gupta C. K., Mukherjee T. K. Hydrometallurgy in extraction processes. CRC Press, 1990, vol. 2, pp. 167—180. DOI: 10.1201/9780203751404.

13. Kryukov V. G. Specific features of ore localization at the Delken gold deposit (Priamurye). Tektonika, glubinnoe stroenie i minerageniya Vostoka Azii: X Kosyginskie chteniya: Materialy Vserossiyskoy konferentsii s mezhdunarodnym uchastiem [Tectonics, Deep Structure and Mineralization of East Asia: X Kosygin Readings. Proceedings of the All-Russian Conference with International Participation], Khabarovsk, 2019, pp. 168—170. [In Russ].

14. Lavrik A. V., Kopylova A. E. Ultrafine forms of gold at the Delken deposit. Vestnik Zabaykal'skogo gornogo kolledzha. 2021, no. 14, pp. 111—114. [In Russ].

15. Lavrik A. V., Rasskazova A. V. Justification of an effective technology for processing Delken gold ore based on mineralogical and technological characteristics. Problemy i perspektivy kompleksnogo osvoeniya i sokhraneniya zemnykh nedr: 5-ya konferentsiya Mezhdunarodnoy nauchnoy shkoly akademika RAN K.N. Trubetskogo [Problems and Prospects of Complex Development and Conservation of the Earth's Subsoil: Proceedings of the 5th Conference of the International Scientific School of Academician K. N. Trubetskoy], Moscow, 2022, pp. 32—35. [In Russ]. DOI: 10.25635/2313-1586.2020.02.017.

16. Hui Li, Wei Xiao, Jianping Jin, Yuexin Han Oxidation roasting of fine-grained carbonaceous gold ore: The effect of aeration rate. Minerals. 2021, vol. 11, no. 6, pp. 543—558. DOI: 10.3390/min11060558.

17. Sazonov A. M., Silyanov S. A., Bayukov O. A., Knyazev Yu.V., Zvyagina E. A., Tishin P. A. Composition and ligand microstructure of arsenopyrite from gold ore deposits of the Yenisei Ridge (Eastern Siberia, Russia). Minerals. 2019, vol. 9, no. 12, pp. 736—755. DOI: 10.3390/min9120737.

18. Vilor N. V., Pavlova L. A., Kaz’min L. A. Aresenopyrite—pyrite paragenesis in gold deposits (thermodynamic modeling). Russian Geology and Geophysics. 2014, vol. 55, pp. 824—841. DOI: 10.1016/j.rgg.2014.06.003.

19. Trigub A. L., Tagirov B. R., Kvashnina K. O., Chareev D. A., Nickolsky M. S., Shiryaev A. A., Baranova N. N., Kovalchuk E. V., Mokhov A. V. X-ray spectroscopy study of the chemical state of «invisible» Au in synthetic minerals in the Fe-As-S system. American Mineralogist. 2017, vol. 102, pp. 1057—1065. DOI: 10.2138/am-2017-5832.

20. Pokrovski G. S., Kara S., Roux J. Stability and solubility of arsenopyrite, FeAsS, in crustal fluids. Geochimica et Cosmochimica Acta. 2002, vol. 66, pp. 2361—2378. DOI: 10.1016/S0016-7037(02)00836-0. 

21. Rogozhnikov D., Karimov K., Shoppert A., Dizer O., Naboichenko S. Kinetics and mechanism of arsenopyrite leaching in nitric acid solutions in the presence of pyrite and Fe(III) ions. Hydrometallurgy. 2021, vol. 199, article 105525. DOI: 10.1016/j.hydromet.2020.105525.

22. Dement'ev V. E., Druzhina G. Ya., Gudkov S. S. Kuchnoe vyshchelachivanie zolota i serebra [Heap leaching of gold and silver], Irkutsk, 2004, 352 p.