Quartz sedimentation volume

Figure 1 shows the volume contraction observed in the settling of a 35% suspension of quartz particles. Also shown is the sediment height of a column of such a suspension of quartz particles. As the sediment volume approaches a constant value (the final compaction volume), the volume contraction ceases as expected. Similar results are obtained with uniformly sized polystyrene spheres. The volume contraction effect is reversible when the polystyrene spheres were resuspended, the total volume increased to the original value as the vicinal hydra-... 

Like other fluorite deposits, the Albigeois ores are notable for their high grade. In veins of the Le Bure deposit, for example, fluorite comprises 90% of the ore volume (Deloule, 1982). Accessory minerals include quartz (SiCh), siderite (FeCCL), chalcopyrite (CuFeSg), and small amounts of arsenopyrite (AsFeS). The deposits occur in a tectonically complex terrain dominated by metamorphic, plutonic, and volcanic rocks and sediments. 

Picer et al. [49] described a method for measuring the radioactivity of labelled DDT contaminated sediments in relatively large volumes of water, using a liquid scintillation spectrometer. Various marine sediments, limestone and quartz in sea water were investigated. External standard ratios and counting efficiencies of the systems investigated were obtained, as was the relation of efficiency factor to external standard ratios for each system studied. 

Szpunar, J., Ceulemans, M., Schmitt, VO., Adams, F.C. and Lobinski, R. (1996) Microwave-accelerated speciation analysis for butyltin compounds in sediments and biomaterials by large volume injection capillary gas chromatography quartz furnace atomic absorption spectrometry. Anal. Chim. Acta, 332, 225-232. 

A 20 pL aliquot of silicon oil (e.g., Serva, Heidelberg, Germany) is placed onto a cleaned sample carrier and allowed to dry, in order to prepare a hydrophobic surface on the quartz carrier to prevent bleeding of the water (acid) drop. Approximately 10 pL of the sample solution are deposited at the centre of the carrier (the volume depends on the type of sediment, its decomposed mass and the dilution after digestion) and dried on a heater adjusted to 100 °C. The special device should be used for positioning the spot correctly in the central area (8 mm diameter) of the carrier. 

The san>e amount of quartz in 25 vol. wet CCI4 (unstable suspension) reached in 15 minutes a final sedimentation height of 53 mm corresponding to 7% by volume of quartz. 

---