Journal of the Royal Society of Western Australia, 87(4), December 2004 
Figure 6. Annotated photomicrographs of standard particles in the fine-grained fraction of wetland sediments. Scale bar on all 
photomicrographs is 100 pm. Photomicrographs of the sand fraction is with reflected light through a stereoscopic microscope using a 
black background to the slide. All photomicrographs of the fine-grained fractions are using plane polarised transmitted light, except for 
(G), in which the light is partly cross-polarised. A. Organic matter (honey brown) in peat from Karrinyup Road Swamp, with scattered 
diatom debris (arrowed). B. Organic matter (brown and light honey brown) in peat from Karrinyup Road Swamp, with vestiges of 
cellular structure (arrowed) in the plant matter. C. Organic matter (dark particles) and sponge spicules and their fragments in peat from 
the shore ot Lake Joondalup. D. Cellular plant material (arrow 1), homogenous plant material (arrow 2), quartz silt (arrow 3), and 
fragments of sponge spicules in a matrix ot diatom silt; sample is the interstitial material from a diatomaceous peaty quartz sand. E. 
Sponge spicules in a diatom silt; sample of diatomite from wetland basin within Bassendean Dunes area east of Yanchep. F. Interstitial 
material from a kaolinitic muddy sand; the dominant mineral is kaolinite, with scattered quartz silt. G. Fine-grained calcite particles 
from a calcilutite. Lake Coogee. H. Carbonate intraclast (arrow 1), broken sponge spicule (arrow 2), and quartz silt (arrow 3) from a 
carbonate intraclastic sediment from Lake Coogee. 
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