Comminution of geological samples using Syalon based milling vessels: comparison with established sample preparation methods

Abstract

The productivity and reputation of analytical laboratories are in part underpinned by the standards of efficiency and quality applied when preparing samples for analysis. Sample milling vessels constructed from Syalon 101 (an aluminium–silicon–oxynitride alloy) have recently become available. This paper describes an assessment of their efficiency and contamination characteristics to assist the evaluation of Syalon as a possible alternative to agate for sample preparation prior to multi-element geochemical analysis. Samples of crushed quartz, quartz sand, garnet-bearing schist and marble were milled in Syalon vibrating-cup and planetary ball mill vessels to compare their comminuting efficiency with that of conventional hardened chromium steel and agate vessels. Contamination during milling was estimated by comparison with samples comminuted in agate vessels only, because metallic preparation equipment is known to introduce contaminants including Fe, Cr, W, Mn, Ni and Co to the sample. The comminuting efficiency of Syalon is superior to that of agate. Although some contamination does occur it may be less analytically critical than that derived from metallic comminution equipment.