4B2 - STD - Lithium Metaborate/Tetraborate Fusion - ICP/MS
Samples fused under code 4B are diluted and analyzed by Perkin Elmer Sciex ELAN 6000, 6100 or 9000 ICP/MS. Three blanks and five controls (three before sample group and two after) are analyzed per group of samples. Duplicates are fused and analyzed every 15 samples. Instrument is recalibrated every 40 samples.
For accurate levels of base metals (Cu, Pb, Zn, Ni and Ag), option 4B1 (see below) is recommended. Option 4B-INAA (see below) is recommended for As, Bs, high W >100 ppm and Cr > 1,000 ppm. Code 5D is recommended for Sn >50 ppm. Mineralized samples should have the "Quant" option (see below) selected or request assays for values which exceed the range of option 4B1.
Code 4B2-std Elements and Detection Limits (ppm)
|
Element
|
Detection Limit
|
Upper Limit
|
|
Element
|
Detection Limit
|
Upper Limit
|
|
Element
|
Detection Limit
|
Upper Limit
|
|
Ag
|
0.5
|
50
|
|
Hf
|
0.2
|
1,000
|
|
Sn
|
1
|
1,000
|
|
As
|
5
|
2,000
|
|
Ho
|
0.1
|
1,000
|
|
Sr
|
2
|
10,000
|
|
Ba
|
3
|
300,000
|
|
In
|
0.2
|
200
|
|
Ta
|
0.1
|
500
|
|
Bi
|
0.4
|
2,000
|
|
La
|
0.1
|
2,000
|
|
Tb
|
0.1
|
1,000
|
|
Ce
|
0.1
|
3,000
|
|
Lu
|
0.04
|
1,000
|
|
Th
|
0.1
|
2,000
|
|
Co
|
1
|
1,000
|
|
Mo
|
2
|
100
|
|
Tl
|
0.1
|
1,000
|
|
Cr
|
20
|
10,000
|
|
Nb
|
1
|
1,000
|
|
Tm
|
0.05
|
1,000
|
|
Cs
|
0.5
|
1,000
|
|
Nd
|
0.1
|
2,000
|
|
U
|
0.1
|
1,000
|
|
Cu
|
10
|
10,000
|
|
Ni
|
20
|
10,000
|
|
V
|
5
|
5,000
|
|
Dy
|
0.1
|
1,000
|
|
Pb
|
5
|
10,000
|
|
W
|
1
|
5,000
|
|
Er
|
0.1
|
1,000
|
|
Pr
|
0.5
|
1,000
|
|
Y
|
1
|
1,000
|
|
Eu
|
0.05
|
1,000
|
|
Rb
|
2
|
1,000
|
|
Yb
|
0.1
|
1,000
|
|
Ga
|
1
|
500
|
|
Sb
|
0.5
|
200
|
|
Zn
|
30
|
10,000
|
|
Gd
|
0.1
|
1,000
|
|
Sm
|
0.1
|
1,000
|
|
Zr
|
5
|
10,000
|
|
Ge
|
1
|
500
|
|
|
|
|
|
|
|
|
Typical ICP/MS Standards Analysis (119 measurements)
|
Element
|
W2
|
Cert.
|
|
Element
|
W2
|
Cert.
|
|
Element
|
W2
|
Cert.
|
|
Element
|
W2
|
Cert.
|
|
V
|
256
|
262
|
|
Y
|
21
|
24
|
|
Ce
|
24
|
24
|
|
Yb
|
2.06
|
20.5
|
|
Cr
|
90
|
93
|
|
Zr
|
99
|
94
|
|
Pr
|
2.5
|
5.9?
|
|
Lu
|
0.33
|
0.33
|
|
Co
|
44
|
44
|
|
Nb
|
7.5
|
7.9
|
|
Nd
|
14
|
14
|
|
Hf
|
2.64
|
2.56
|
|
Ni
|
67
|
70
|
|
Mo
|
0.7
|
0.6
|
|
Sm
|
3.38
|
3.25
|
|
Ta
|
0.5
|
0.5
|
|
Cu
|
105
|
103
|
|
Ag
|
<0.5
|
0.05
|
|
Eu
|
1.1
|
1.1
|
|
W
|
<0.2
|
0.3
|
|
Zn
|
72
|
77
|
|
In
|
<0.2
|
-
|
|
Gd
|
3.5
|
3.6
|
|
Tl
|
0.1
|
0.2
|
|
Ga
|
18
|
20
|
|
Sn
|
<0.5
|
-
|
|
Tb
|
0.62
|
0.63
|
|
Pb
|
8
|
9.3
|
|
Ge
|
2
|
1
|
|
Sb
|
0.78
|
0.79
|
|
Dy
|
3.8
|
3.8
|
|
Bi
|
<0.05
|
0.03
|
|
As
|
<5
|
1.24
|
|
Cs
|
0.95
|
0.99
|
|
Ho
|
0.76
|
0.76
|
|
Th
|
2.3
|
2.5
|
|
Rb
|
20
|
20
|
|
Ba
|
164
|
182
|
|
Er
|
2.3
|
2.5
|
|
U
|
0.49
|
0.53
|
|
Sr
|
193
|
194
|
|
La
|
11.3
|
11.4
|
|
Tm
|
0.32
|
0.38
|
|
|
|
|
Code 4B2-std Options
Quant
A 1 g sample is digested with aqua regia and diluted to 250 ml volumetrically. Appropriate international reference materials for the metals of interest are digested at the same time. The samples and standards are analyzed on a Varian Vista 735 or a Thermo ICAP 6500 ICP.
4B1 – Base Metals
A 0.25 g sample is digested with four acids beginning with hydrofluoric, followed by a mixture of nitric and perchloric acids, heated using precise programmer controlled heating in several ramping and holding cycles which takes the samples to dryness. After dryness is attained, samples are brought back into solution using hydrochloric acid. With this digestion certain phases may be only partially solubilized. These phases include zircon, monazite, sphene, gahnite, chromite, cassiterite, rutile and barite. Ag greater than 50 ppm and Pb greater than 5,000 ppm should be assayed as high levels may reprecipitate. Only sulphide sulfur will be solubilized.
In-lab standards (traceable to certified reference materials) or certified reference materials are used for quality control.
Samples are analyzed using a Varian Vista 735 ICP.
Option 4B1 Elements and Detection Limits (ppm)
|
Element
|
Detection Limit
|
Upper Limit
|
|
S
|
0.001%
|
20%
|
|
Ni
|
1
|
10,000
|
|
Zn
|
1
|
10,000
|
|
Cu
|
1
|
10,000
|
|
Cd
|
0.5
|
2,000
|
|
Ag
|
0.5
|
50
|
|