Wikipedia:Picture peer review/Diatomaceous earth

Diatomaceous earth

Original - Diatomaceous earth, also known as diatomite or kieselgur, as viewed under bright field illumination on a light microscope. Diatomaceous earth is a soft, siliceous, sedimentary rock made up of the cell walls/shells of single cell diatoms and readily crumbles to a fine powder. It is essentially entirely made up of microfossils. Diatom cell walls are bivalve, i.e. made up of two halves, and are made up of biogenic silica; silica synthesised in the diatom cell by the polymerisation of silicic acid. This sample consists of a mixture of centric (radially symmetric) and pennate (bilaterally symmetric) diatoms. The primary uses of diatomaceous earth are for cleaning (scouring), filtration, heat-resistive insulation and as an inert absorbent substrate. One of the most famous uses was by Alfred Nobel who developed dynamite; a mixture of diatomaceous earth and nitroglycerin. This image of diatomaceous earth particles in water is at a scale of 6.236 pixels/μm, the entire image covers a region of approximately 1.13 by 0.69 mm.

This is a high quality micrograph of a common and widely used substance presented in unusually high detail.

Articles this image appears in

Diatomaceous earth, Dynamite, Silicate, Diatom, Micropaleontology and Biogenic silica.

Creator

Richard Wheeler (Zephyris)

Suggested by

- Zephyris _Talk 21:44, 10 July 2010 (UTC)

Comments

• Note that there are also two alternative versions available, one using dark field illumination and the other using phase contrast illumination.

• 
  Bright field image (as on the right).
• 
  Dark field image.
• 
  Phase contrast image.

• I would specifically be interested in comments on scale and cropping; this is very large image with great detail and I am struggling to decide which balance would be best, easily visible detail (cropping to a small area) or a greater sense of scale (full image with ~1mm field of view). - Zephyris _Talk 21:48, 10 July 2010 (UTC)
• I should have also said this is a stitched montage of 30 images (6x5) so keep an eye out for stitching artefacts. These are pretty impossible to avoid (the whole sample is undergoing brownian motion) but it would be good to know about serious problems. - Zephyris _Talk 21:54, 10 July 2010 (UTC)

Seconder

• FPC adores "science-y" stuff like this, and I love how great the quality is for such a very large image and many people on FPC are strongly biased toward really big images. I don't think you'd meet with much resistance if you nominated this. --I′d※<3※Ɵɲɛ (talk) 00:53, 18 July 2010 (UTC)
• Now nominated at FPC. --jjron (talk) 19:23, 31 July 2010 (UTC)