AS 4030.3-2002

1 - AS 4030.3-2002 LEAD SULFIDE CONCENTRATES-CHEMICAL ANALYSIS - DETERMINATION OF SILVER AND GOLD CONTENTS-FIRE ASSAY AND FLAME A
4 - PREFACE
5 - CONTENTS
7 - 1 Scope
7 - 2 Normative references
7 - 3 Principle
7 - 3.1 Scorification
8 - 3.2 Cupellation
8 - 4 Reagents
8 - 4.1 Sodium carbonate
8 - 4.2 Litharge
8 - 4.3 Silica
8 - 4.4 Potassium nitrate or sodium nitrate
8 - 4.5 Flour
8 - 4.6 Nitric acid
8 - 4.7 Nitric acid wash solution
8 - 4.8 Nitric acid
8 - 4.9 Hydrochloric acid
8 - 4.10 Borax
8 - 4.11 Silver metal
8 - 4.12 Gold metal
8 - 4.13 Aqua regia
8 - 4.14 Ammonia solution
8 - 4.15 Sodium chloride
8 - 4.16 Standard solutions
9 - 4.16.1 Silver standard solutions
9 - 4.16.2 Gold standard solutions
9 - 4.17 Calibration solutions
9 - 4.17.1 Silver calibration solutions
10 - 4.17.2 Gold calibration solutions
10 - 5 Apparatus
10 - 5.1 Volumetric glassware,
10 - 5.2 Conventional fire assay equipment
10 - 5.2.1 Assay crucible furnace
10 - 5.2.2 Muffle furnace
10 - 5.2.3 Crucibles
10 - 5.2.4 Scorifiers
10 - 5.2.5 Cupels
10 - 5.2.6 Conical mould
10 - 5.2.7 Pulverizer
10 - 5.3 Balances
10 - 5.3.1 Top loading
10 - 5.3.2 Precision analytical
10 - 5.4 Atomic absorption spectrometer (AAS)
10 - 5.5 Filtration equipment
10 - 5.5.1 Membrane filter - cellulose nitrate/cellulose acetate
10 - 5.5.2 Vacuum flask
10 - 5.5.3 Membrane filter funnel
10 - 5.6 Burette
11 - 6 Sample
11 - 6.1 Test sample
11 - 6.2 Test portion
11 - 7 Procedure
11 - 7.1 Number of determinations
11 - 7.2 Trial fusion
11 - 7.3 Blank tests
11 - 7.4 Charge preparation
12 - 7.5 Primary fusion
12 - 7.6 Selection of recovery procedure
13 - 7.7 Scorification
13 - 7.7.1 General
13 - 7.7.2 Retreatment fusion
13 - 7.7.3 Scorification
13 - 7.8 Cupellation
13 - 7.8.1 General
14 - 7.8.2 Retreatment fusion
14 - 7.8.3 Cupellation
14 - 7.9 Treatment of the lead buttons or silver/gold beads
14 - 7.10 Determination of silver in the test solution by flame atomic absorption spectrometry
15 - 7.11 Determination of gold in the test solution by flame atomic absorption spectrometry
16 - 8 Expression of results
16 - 8.1 Silver content
16 - 8.2 Gold content
16 - 9 Precision
16 - 9.1 Expression of precision
17 - 9.2 Method for obtaining the final result
17 - 9.3 Precision between laboratories
18 - 9.4 Check of trueness
19 - 10 Test report
20 - Annex A - Procedure for the preparation and determination of the mass of a predried test portion
20 - A.1 Scope
20 - A.2 Principle
20 - A.3 Reagents
20 - A.4 Apparatus
20 - A.5 Procedure
20 - A.5.1 Preparation of the weighing vessel
20 - A.5.2 Test portion
21 - A.5.3 Determination of the test portion dry mass
21 - A.6 Calculation of the test portion dry mass
22 - Annex B - Trial fusion
22 - B.1 Introduction
22 - B.2 Procedure
23 - Annex C - Blank determination
23 - C.1 Introduction
23 - C.2 Procedure
24 - Annex D - Flowsheet of the procedure for the acceptance of analytical values for the test samples
25 - Annex E - Derivation of precision equations
25 - E.1 Introduction
25 - E.2 Design of test programme
25 - E.3 Test samples
25 - E.4 Statistical evaluation
32 - Annex F - Bibliography