HALOGENS
Halogen analysis is a great tool to aid with exploration. Our mineral testing laboratory offers halogen analysis by INAA (short-lived Isotopes) or by fusion with ISE analysis.
A 0.2g sample is fused with a combination of lithium metaborate and lithium tetraborate in an induction furnace to release the chloride ions from the sample matrix. The fuseate is dissolved in dilute nitric acid, prior to analysis the ion strength of the solution is adjusted. The chloride ion electrode is immersed in this solution to measure the fluoride-ion activity directly.
| Analysis | Method | Detection Limit |
|---|---|---|
| Cl (ISE) | FUS-ISE | 0.01% |
A 0.2g sample is fused with a combination of lithium metaborate and lithium tetraborate in an induction furnace to release the fluoride ions from the sample matrix. The fuseate is dissolved in dilute nitric acid, prior to analysis the solution is complexed and the ionic strength adjusted with an ammonium citrate buffer. The fluoride ion electrode is immersed in this solution to measure the fluoride-ion activity directly. An automated fluoride analyzer from Mandel Scientific is used for the analysis.
| Analysis | Method | Detection Limit |
|---|---|---|
| F | FUS-ISE | 0.01% |
1g samples are weighed into medium poly vials and are irradiated at a thermal flux of 7 x 1012 n cm-2s-1 in a computer controlled rabbit system, which sends the INAA vials directly to the source of irradiation then back to the fume hood in the lab for analysis. After appropriate decay times to allow aluminum and other very short lived isotopes to decay, the samples are counted sequentially for the analyte(s) of interest. Values are corrected for decay and compared to a standard calibration. Minimum of two standards are analyzed with every work order. Duplicates are analyzed when samples are provided.
Elements and Detection Limits (ppm)
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Al | 1 | 100,000 |
| Br | 5 | 10,000 |
| Cl | 100 | 100,000 |
| Cu | 5 | 2,500 |
| Dy | 0.5 | 5,000 |
| Ga | 5 | 10,000 |
| I | 0.5 | 5,000 |
| In | 0.1 | 5,000 |
| Mg | 0.05% | 50% |
| Mn | 0.1 | 10,000 |
| Na | 50 | 200,000 |
| Re | 1 | 5,000 |
| Ti | 50 | 100,000 |
| V | 0.1 | 10,000 |
Reference:
Hoffman, E.L., 1992. Instrumental Neutron Activation in Geoanalysis. Journal of Geochemical Exploration, volume 44, pp. 297-319.
