Au-Isomer Industrial Gold ore assay system GAMMA ACTIVATION ANALYSIS OF GOLD ORES


Gamma activation analysis (GAA) is an irradiation of large-mass ore samples (300-500 g) with high-energy gamma quanta, generated by linear electron accelerator (LINAC), followed by recording the induced activity of excited gold nuclei (isomers) using a gamma spectrometer.


  • The ability to analyze large ore samples with a volume of 300-500 cm^3;
  • Feasibility to analyze ore particles with sizes up to 3.0 mm, due to high penetrating power of gamma radiation;
  • Analysis duration does not exceed 20-30 s, thanks to short half-life of excited gold nuclei;
  • High representativeness of GAA in comparison with chemical analysis;
  • Guaranteed high sensitivity and accuracy of analysis;
  • High analysis selectivity, due to using large-area high-resolution semiconductor detectors;
  • High productivity of analysis (up to 1000 analyzes per day);
  • Non-destructive nature of analysis, thereby the analysis can be repeated many times;
  • Analysis results practically do not depend on chemical composition of a sample;
  • Induced activity of the sample decreases to background levels in several minutes after the analysis is finished;
  • The ability to analyze other elements simultaneously with gold (Ag, Cu, Se, Br, Ba, Y, Pb, Hf, W, etc.).


Gold detection limit achieved at the Au-Isomer facility with a single irradiation of certified low-background samples, was 0.017 - 0.019 g/t!


  1. Muruntau (Uzbekistan), 1977 — operational commissioning;
  2. Magadan (Russia), 1979 — operational commissioning;
  3. Batagay (Russia), 1986 — operational commissioning;
  4. Tommot (Russia), 1989 — prepared for commissioning, but not commissioned;
  5. Muruntau (Uzbekistan), 2017-2020 — modernization of LINAC and registration system;
  6. Pavlik (Russia), 2021 — fabrication of the Au-Isomer facility and performance of tests;
  7. Pavlik (Russia), 2022 — operational commissioning of the new laboratory.


Gold detection limit, g/t0,03
Measurement accuracy for ore with gold content of 1 g/t
- with gold content of 10 g/t
Performance for samples with gold content ≥1 ppm, samples/hour70
Sample volume, ml 300
Ore particles size of not more than, mm 3
Energy of electrons at the linear accelerator output, MeV7-9
Maximum power of the electron beam, kW10
Radiation background on surface of safety barrier, μSv/h ≤1
Facility height with a crane for the assembly of radiation shielding, m 4.1
Facility area, m24 х 7
Facility weight with shielding, t118
Maximum power consumption, kW70