Other base metals

Base metals beyond nickel & copper

Base metals are derived from a range of deposit types and host rocks. The lithologies hosting mineralisation range from carbonates, clastic sediments, and igneous rocks. The choice of analysis for base metals of interest will depend on sample mineralogy and concentration of the elements of interest. Tin, in particular, is often hosted in cassiterite a mineral that is highly resistant to acid digestion, and barite is also acid resistant, therefore a fusion method is necessary for full recovery.

Outros metais básicos

Exploration samples

Exploration samples benefit from detection limits that can characterise background with a high degree of precision. Greenfields exploration will often need super-trace detection level methods that are described in our Generative Exploration section, but for exploration where background values are known to be higher, alternative methods can be used.

Analysis methods for exploration samples

ALS offers methods from both four-acid (ME-MS61™) and aqua regia digestions (ME-MS41™) that are analysed via ICP-MS instrumentation for sensitive detection limits, with trace level options measured by ICP-AES (ME-ICP61 and ME-ICP41). Fusion decomposition for base metals is best accomplished via an oxidising flux to ensure full recovery, such as trace level sodium peroxide fusion method ME-MS89L™ or ME-ICP81 for higher grade samples.

Trace level aqua regia method

Code Analytes & Ranges (ppm)
ME-MS41™
0.5g sample		 Ag 0.01-100 Cs 0.05-500 Mo 0.05-10,000 Sr 0.2-10,000
Al 0.01-25% Cu 0.2-10,000 Na 0.01%-10% Ta 0.01-500
As 0.1-10,000 Fe 0.01%-50% Nb 0.05-500 Te 0.01-500
Au* 0.02-25 Ga 0.05-10,000 Ni 0.2-10,000 Th 0.2-10,000
B 10-10,000 Ge 0.05-500 P 10-10,000 Ti 0.005%-10%
Ba 10-10,000 Hf 0.02-500 Pb 0.2-10,000 Tl 0.02-10,000
Be 0.05-1,000 Hg 0.01-10,000 Rb 0.1-10,000 U 0.05-10,000
Bi 0.01-10,000 In 0.005-500 Re 0.001-50 V 1-10,000
Ca 0.01%-25% K 0.01%-10% S 0.01%-10% W 0.05-10,000
Cd 0.01-1,000 La 0.2-10,000 Sb 0.05-10,000 Y 0.05-500
Ce 0.02-500 Li 0.1-10,000 Sc 0.1-10,000 Zn 2-10,000
Co 0.1-10,000 Mg 0.01%-25% Se 0.2-1,000 Zr 0.5-500
Cr 1-10,000 Mn 5-50,000 Sn 0.2-500


Trace level four acid method

Code Analytes & Ranges (ppm)
ME-MS61™
0.25g sample		 Ag 0.01-100 Cu 0.2-10,000 Na 0.01%-10% Sr 0.2-10,000
Al 0.01%-50% Fe 0.01%-50% Nb 0.1-500 Ta 0.05-500
As 0.2-10,000 Ga 0.05-10,000 Ni 0.2-10,000 Te 0.05-500
Ba 10-10,000 Ge 0.05-500 P 10-10,000 Th 0.01-10,000
Be 0.05-1,000 Hf 0.1-500 Pb 0.5-10,000 Ti 0.005%-10%
Bi 0.01-10,000 In 0.005-500 Rb 0.1-10,000 Tl 0.02-10,000
Ca 0.01%-50% K 0.01%-10% Re 0.002-50 U 0.1-10,000
Cd 0.02-1,000 La 0.5-10,000 S 0.01%-10% V 1-10,000
Ce 0.01-500 Li 0.2-10,000 Sb 0.05-10,000 W 0.1-10,000
Co 0.1-10,000 Mg 0.01%-50% Sc 0.1-10,000 Y 0.1-500
Cr 1-10,000 Mn 5-100,000 Se 1-1,000 Zn 2-10,000
Cs 0.05-500 Mo 0.05-10,000 Sn 0.2-500 Zr 0.5-500

Base metal sulphides

Mineralisation, even at moderate grades, may require methods that are suited for high concentrations of the elements of interest. These methods will often have added oxidising reagents to ensure sulphides are fully decomposed.

Base metal sulphide analysis

Methods for low-grade ore analysis include four-acid (ME-ICP61a) and aqua regia (ME-ICP41a) decompositions measured using ICP-AES spectroscopy. Both methods target the portion of the sample that is digested by the acid combination used. For full decomposition, fusion with sodium peroxide and ICP-AES is recommended (ME-ICP81).

Ore grade aqua regia method

Code Analytes & Ranges (ppm)
ME-ICP41a
0.4g sample		 Ag 1-200 Cr 5-50,000 Mo 5-50,000 Th 100-50,000
Al 0.05%-50% Cu 5-50,000 Na 0.05%-50% Ti 0.05%-50%
As 10-100,000 Fe 0.05%-50% Ni 5-50,000 Tl 50-50,000
Ba 50-50,000 Ga 50-50,000 P 50-50,000 U 50-50,000
Be 5-500 Hg 5-50,000 Pb 10-50,000 V 5-50,000
Bi 10-50,000 K 0.05%-50% S 0.05%-10% W 50-50,000
Ca 0.05%-50% La 50-50,000 Sb 10-50,000 Zn 10-50,000
Cd 5-2,500 Mg 0.05%-50% Sc 5-50,000
Co 5-50,000 Mn 25-50,000 Sr 5-50,000


Ore grade four acid method

Code Analytes & Ranges (ppm)
ME-ICP61a
0.4g sample		 Ag 1-200 Cr 10-100,000 Na 0.05%-30% Ti 0.05%-30%
Al 0.05%-30% Cu 10-100,000 Ni 10-100,000 Tl 50-50,000
As 50-100,000 Fe 0.05%-50% P 50-100,000 U 50-50,000
Ba 50-50,000 Ga 50-50,000 Pb 20-100,000 V 10-100,000
Be 10-10,000 K 0.1%-30% S 0.05%-10% W 50-50,000
Bi 20-50,000 La 50-50,000 Sb 50-50,000 Zn 20-100,000
Ca 0.05%-50% Mg 0.05%-50% Sc 10-50,000
Cd 10-10,000 Mn 10-100,000 Sr 10-100,000
Co 10-50,000 Mo 10-50,000 Th 50-50,000

High grade samples

At ore grade concentrations, higher analytical precision is often sought as opposed to analyses for purely exploration applications. At ALS, ore grade methods have tighter quality control limits built-in to provide confidence in important high grade values. Dependent on your needs, ALS offers a selection of suitable methods.

Base metal ore methods

For high grade base metal ores, particularly massive sulphides, we recommend methods utilising oxidising agents such as sodium peroxide with ICP-AES (method ME-ICP81) which will report up to 30% Pb, 20% Sn and 60% Zn amongst other analytes. Other suitable alternatives include ME-ICPORE that includes a strong oxidising digestion with ICP-AES analysis, or a fusion with XRF analysis via methods ME-XRF15 and ME-XRF15c for concentrates. For single element determinations classical chemistry techniques are available.

Ore grade oxidising digestion method

Code Analytes & Ranges (ppm)
ME-ICPORE Ag 1-1500ppm Co 0.001-20 Mn 0.005-50 S 0.05-50
As 0.005-30 Cu 0.001-40 Mo 0.001-10 Sb 0.005-100
Bi 0.005-30 Fe 0.01-100 Ni 0.001-30 Tl 0.005-1
Ca 0.01-50 Hg 8-10000ppm P 0.01-20 Zn 0.002-100
Cd 0.001-10 Mg 0.01-50 Pb 0.005-30

Frequently asked questions

Related resources

Generative Exploration

Super trace detection limits

At early stages of exploration, or in regions where alteration has very low concentrations of pathfinder elements, the lowest detection limits may be needed.

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Mineralogy studies

ALS has expert teams for mineralogy studies for all stages of exploration and mining.

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