AQUA REGIA “PARTIAL” DIGESTION
This leach uses a combination of concentrated hydrochloric and nitric acids to leach sulphides, some oxides and some silicates.
Mineral phases which are hardly (if at all) attacked include barite, zircon, monazite, sphene, chromite, gahnite, garnet, ilmenite, rutile and cassiterite. The balance of silicates and oxides are only slightly to moderately attacked, depending on the degree of alteration. Generally, but not always, most base metals and gold are usually dissolved.
0.5g of sample is digested with aqua regia. The sample is then cooled and diluted with deionized water. The samples are then analyzed using an ICP for the 35 element suite. QC for the digestion is 15% for each batch, 2 method reagent blanks, 6 in-house controls, 8 sample duplicates and 5 certified reference materials. An additional 20% QC is performed as part of the instrumental analysis to ensure quality in the areas of instrumental drift.
Elements and Detection Limits (ppm)
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ag | 0.2 | 100 |
| Al | 0.01% | 10% |
| As | 2 | 10,000 |
| Ba | 1 | - |
| Be | 1 | 1,000 |
| Bi | 10 | - |
| Ca | 0.01% | 10% |
| Cd | 0.5 | 2,000 |
| Co | 1 | 10,000 |
| Cr | 2 | - |
| Cu | 1 | 10,000 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Fe | 0.01% | 50% |
| K | 0.01% | 10% |
| Mg | 0.01% | 25% |
| Mn | 2 | 100,000 |
| Mo | 2 | 10,000 |
| Na | 0.01% | - |
| Ni | 1 | 10,000 |
| P | 0.001% | 10 |
| Pb | 2 | 5,000 |
| S+ | 0.01% | 20% |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Sb | 10 | - |
| Sc | 1 | 10,000 |
| Sn | 10 | - |
| Sr | 1 | 10,000 |
| Ti | 0.01% | 20% |
| V | 1 | 1000 |
| W | 10 | - |
| Y | 1 | 1000 |
| Zn | 1 | 10,000 |
| Zr | 1 | - |
Notes:
Extraction of of each element by Aqua Regia Digestion is dependent on mineralogy .
+ Sulphide sulphur and soluble sulphates are extracted.
Assays are recommended for values which exceed the upper limits.
0.5g of sample is digested with aqua regia. The sample is cooled and then diluted with deionized water. The samples are then analyzed using an ICP for the 38 element suite. QC for the digestion is 15% for each batch, 2 method reagent blanks, 6 in-house controls, 8 sample duplicates and 5 certified reference materials. An additional 20% QC is performed as part of the instrumental analysis to ensure quality in the areas of instrumental drift.
Elements and Detection Limits (ppm except where noted)
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ag | 0.2 | 100 |
| Al | 0.01% | 8% |
| As | 2 | 10,000 |
| B | 10 | 10,000 |
| Ba | 10 | 10,000 |
| Be | 0.5 | 1000 |
| Bi | 2 | 10,000 |
| Ca | 0.01% | 10% |
| Cd | 0.5 | 2,000 |
| Co | 1 | 10,000 |
| Cr | 1 | 10,000 |
| Cu | 1 | 10,000 |
| Fe | 0.01% | 30% |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ga | 10 | 10,000 |
| Hg | 1 | 10,000 |
| K | 0.01% | 10% |
| La | 10 | 10,000 |
| Mg | 0.01% | 25% |
| Mn | 5 | 100,000 |
| Mo | 1 | 10,000 |
| Na | 0.001% | 10% |
| Ni | 1 | 10,000 |
| P | 0.001% | 5% |
| Pb | 2 | 5,000 |
| S+ | 0.01% | 20% |
| Sb | 2 | 10,000 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Sc | 1 | 10,000 |
| Sr | 1 | 10,000 |
| Te | 1 | 500 |
| Th | 20 | 10,000 |
| Ti | 0.01% | 10% |
| Tl | Tl | 10,000 |
| U | 10 | 10,000 |
| V | 1 | 10,000 |
| W | 10 | 200 |
| Y | 1 | 1000 |
| Zn | 2 | 10,000 |
| Zr | 1 | 10,000 |
Notes:
Extraction of each element by Aqua Regia Digestion is dependent on mineralogy.
+ Sulphide sulphur and soluble sulphates are extracted.
Assays are recommended for values which exceed the upper limits.
A 0.5g sample is digested in aqua regia in a microprocessor-controlled digestion block. Digested samples are diluted and analyzed by an ICP-MS. One blank is run for every 68 samples. An in-house control sample is run every 33 samples. Digested standards are run every 68 samples. After every 15 samples, a digestion duplicate is analyzed. Instrument is recalibrated every 68 samples.
Elements and Detection Limits (ppm, except where noted)
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ag | 0.1 | 100 |
| Al | 0.01% | 8% |
| As | 0.5 | 10,000 |
| Au | 0.5 ppb | 1,000 ppb |
| B | 20 | 2,000 |
| Ba | 1 | 10,000 |
| Bi | 0.1 | 2,000 |
| Ca | 0.01% | 25% |
| Cd | 0.1 | 2,000 |
| Co | 0.1 | 5,000 |
| Cr | 1 | 10,000 |
| Cu | 0.2 | 10,000 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Fe | 0.01 % | 30 % |
| Ga | 1 | 1,000 |
| Hg | 0.01 | 50 |
| K | 0.01% | 5% |
| La | 1 | 10,000 |
| Mg | 0.01% | 10% |
| Mn | 1 | 10,000 |
| Mo | 0.1 | 10,000 |
| Na | 0.001% | 5% |
| Ni | 0.1 | 10,000 |
| P | 0.001% | 5% |
| Pb | 0.1 | 5,000 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| S+ | 0.25% | 20% |
| Sb | 0.1 | 500 |
| Sc | 0.1 | 10,000 |
| Se | 0.5 | 10,000 |
| Sr | 1 | 5,000 |
| Te | 0.2 | 500 |
| Th | 0.1 | 200 |
| Ti | 0.01% | 10% |
| Tl | 0.1 | 500 |
| V | 2 | 1,000 |
| W | 0.1 | 200 |
| Zn | 1 | 5,000 |
Note: Assays are recommended for values which exceed the upper limits.
Au is semi-quantitative due to the small sample size.
Extraction of each element by Aqua Regia Digestion is dependent on mineralogy.
+ Sulphide sulphur and soluble sulphates are extracted.
A 0.5g sample is digested in aqua regia in a microprocessor controlled digestion block. Digested samples are diluted and analyzed by an ICP-MS. One blank is run for every 68 samples. An in-house control is run every 33 samples. Digested standards are run every 68 samples. After every 15 samples, a digestion duplicate is analyzed. Instrument is recalibrated every 68 samples.
Elements and Detection Limits (ppm)
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ag | 0.002 | 100 |
| Al | 0.01% | 8% |
| As | 0.1 | 10,000 |
| Au | 0.5 ppb | 10,000 ppb |
| B | 1 | 5,000 |
| Ba | 0.5 | 6,000 |
| Be | 0.1 | 1,000 |
| Bi | 0.02 | 2,000 |
| Ca | 0.01% | 25% |
| Cd | 0.1 | - |
| Co | 0.1 | 5,000 |
| Cr | 1 | 10,000 |
| Cs | 0.02 | 500 |
| Cu | 0.2 | 10,000 |
| Dy | 0.1 | 1000 |
| Er | 0.1 | 1000 |
| Eu | 0.1 | 100 |
| Fe | 0.01% | 30% |
| Ga | 0.02 | 500 |
| Gd | 0.1 | 1000 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| Ge | 0.1 | 500 |
| Hf | 0.1 | 500 |
| Hg | 10 | 10,000 ppb |
| Ho | 0.1 | 1000 |
| In | 0.02 | 500 |
| K | 0.01% | 5% |
| La | 0.5 | 10,000 |
| Li | 0.1 | 10,000 |
| Lu | 0.1 | 100 |
| Mg | 0.01% | 10% |
| Mn | 1 | 10,000 |
| Mo | 0.01 | 10,000 |
| Na | 0.001% | 5% |
| Nb | 0.1 | 500 |
| Nd | 0.02 | 5000 |
| Ni | 0.1 | 10,000 |
| P | 0.001% | 5% |
| Pb | 0.1 | 5,000 |
| Pr | 0.1 | 1000 |
| Rb | 0.1 | 500 |
| Re | 0.001 | 100 |
| Element | Detection Limit | Upper Limit |
|---|---|---|
| S+ | 0.25% | 20% |
| Sb | 0.02 | 500 |
| Sc | 0.1 | 10,000 |
| Se | 0.1 | 10,000 |
| Sm | 0.1 | 100 |
| Sn | 0.05 | 200 |
| Sr | 0.5 | 5,000 |
| Ta | 0.05 | 50 |
| Tb | 0.1 | 100 |
| Te | 0.02 | 500 |
| Th | 0.1 | 200 |
| Ti | 0.001% | 10% |
| Tl | 0.02 | 500 |
| Tm | 0.1 | 1,000 |
| U | 0.1 | 10,000 |
| V | 1 | 1,000 |
| W | 0.1 | 200 |
| Y | 0.01 | 500 |
| Yb | 0.1 | 200 |
| Zn | 0.1 | 5,000 |
| Zr | 0.1 | 5,000 |
Notes:
Au is semi-quantitative due to the small sample size.
Extraction of each element by Aqua Regia Digestion is dependent on mineralogy.
Unaltered silicates and resistate minerals may not be dissolved.
+ Sulphide sulphur and soluble sulphides are extracted.
A 0.5g sample is digested in aqua regia in a microprocessor controlled digestion block. The solution is diluted and analyzed by ICP-MS. One blank is run for every 68 samples. An in-house control is run every 33 samples. Digested standards are run every 68 samples. After every 15 samples, a digestion duplicate is analyzed. Instrument is recalibrated every 68 samples.
Certain elements (Ti, P and S) are analyzed by ICP-OES. This extends the dynamic range for a number of elements as well. International certified reference materials are analyzed at the beginning and end of each batch of samples. Internal control standards are analyzed every 10 samples and a duplicate is run for every 10 samples. This digestion is not total and will not dissolve silicates some oxides and resistate minerals (e.g., zircon, monazite, sphene, etc.).
| Element | Detection Limit | Upper Limit | Reported By |
|---|---|---|---|
| Ag | 0.002 | 100 | ICP/MS |
| Al | 0.01% | 8% | ICP/MS |
| As | 0.1 | 10,000 | ICP/MS |
| Au | 0.5 ppb | 10,000 ppb | ICP/MS |
| B | 1 | 5,000 | ICP/MS |
| Ba | 0.5 | 6,000 | ICP/MS |
| Be | 0.1 | 1,000 | ICP/MS |
| Bi | 0.02 | 2,000 | ICP/MS |
| Ca | 0.01% | 25% | ICP/MS |
| Cd | 0.01 | 1,000 | ICP/MS |
| Ce | 0.01 | 10,000 | ICP/MS |
| Co | 0.1 | 5,000 | ICP/MS |
| Cr | 1 | 10,000 | ICP/MS |
| Cs | 0.02 | 500 | ICP/MS |
| Cu | 0.2 | 10,000 | ICP/MS |
| Dy | 0.1 | 1,000 | ICP/MS |
| Er | 0.1 | - | ICP/MS |
| Eu | 0.1 | - | ICP/MS |
| Fe | 0.01% | 30% | ICP/MS |
| Ga | 0.02 | 500 | ICP/MS |
| Ge | 0.1 | 500 | ICP/MS |
| Gd | 0.1 | 1,000 | ICP/MS |
| Hf | 0.1 | 500 | ICP/MS |
| Hg | 10 | 10,000 ppb | ICP/MS |
| Ho | 0.1 | 1,000 | ICP/MS |
| In | 0.02 | 500 | ICP/MS |
| K | 0.01% | 5% | ICP/MS |
| La | 0.5 | 1,000 | ICP/MS |
| Li | 0.1 | 10,000 | ICP/MS |
| Lu | 0.1% | 100 | ICP/MS |
| Mg | 0.01% | 10% | ICP/MS |
| Mn | 1 | 10,000 | ICP/MS |
| Element | Detection Limit | Upper Limit | Reported By |
|---|---|---|---|
| Mo | 0.01 | 10,000 | ICP/MS |
| Na | 0.001% | 5% | ICP/MS |
| Nb | 0.1 | 500 | ICP/MS |
| Nd | 0.02 | 5,000 | ICP/MS |
| Ni | 0.1 | 10,000 | ICP/MS |
| P | 0.001% | 5% | ICP |
| Pb | 0.1 | 5,000 | ICP/MS |
| Pr | 0.1 | 1,000 | ICP/MS |
| Rb | 0.1 | 500 | ICP/MS |
| Re | 0.001 | 100 | ICP/MS |
| S+ | 0.001% | 20% | ICP |
| Sb | 0.02 | 500 | ICP/MS |
| Sc | 0.1 | 10,000 | IPC/MS |
| Se | 0.1 | 10,000 | ICP/MS |
| Sm | 0.1 | 100 | ICP/MS |
| Sn | 0.05 | 200 | ICP/MS |
| Sr | 0.5 | 5,000 | ICP/MS |
| Ta | 0.05 | 50 | ICP/MS |
| Tb | 0.1 | 100 | ICP/MS |
| Te | 0.02 | 500 | ICP/MS |
| Th | 0.1 | 200 | ICP/MS |
| Ti | 0.01% | 10% | ICP |
| Tl | 0.02 | 500 | ICP/MS |
| Tm | 0.1 | 1,000 | IPC/MS |
| U | 0.1 | 10,000 | ICP/MS |
| V | 1 | 1,000 | ICP/MS |
| W | 0.1 | 200 | ICP/MS |
| Y | 0.01 | 500 | ICP/MS |
| Yb | 0.1 | 200 | ICP/MS |
| Zn | 0.1 | 5,000 | ICP/MS |
| Zr | 0.1 | 5,000 | ICP/MS |
Notes:
Au is semi-quantitative due to the small sample size.
Extraction of each element by Aqua Regia Digestion is dependent on mineralogy.
Unaltered silicates and resistate minerals may not be dissolved.
+ Sulphide sulphur and soluble sulphates are extracted.
If any elements are over-range, an aqua regia assay can be performed
Assays provide quantitative determinations of elements in non-processed geological materials. Assays are usually required when samples are known or suspected to contain higher levels of metals.
A 0.5g sample is digested in aqua regia and diluted volumetrically to 250 ml with 18 megaohm water. Certified reference materials for the appropriate elements are digested the same way and are used as a verification standard(s). Samples are analyzed on an ICP-OES.
Code 8 – AR – ICP-OES Elements and Detection Limits
| Element | Detection Limit |
|---|---|
| Ag | 3 ppm |
| As | 0.01 |
| Cd | 0.003 % |
| Co | 0.003 % |
| Cu | 0.001 % |
| Fe | 0.003 % |
| Hg | 0.001 % |
| Ni | 0.003 % |
| Pb | 0.003 % |
| Zn | 0.001 % |
Note: Extraction for Aqua Regia is dependent on mineralogy.
