The ideal slide contains particle sizes range between 0 and 30µm with an even spatial distribution throughout this slide. The gap between individual particles should be sufficient to able nannofossils to be easily located and identified.
The particle size variation must be constant between nannologist, but can be modified according to the age of sediments. The size variation may be controlled by the time allowed for settling from suspension , prior to pipetting of the sample. The spatial distribution of particles may be vary between nannologist and can be influenced by the quantity of distilled water used to process the sample.
- Wrap the small but representative sample in a paper towel..
- Crush it gently using a small hammer.
- Place the crushed sediment into a beaker and add distilled water. Soak it for 12 hours.
- Decant the suspension into a labelled test-tube and place into a centrifuge.
- Stop the centrifuge immediately after spinning it at 350 rpm for 30 seconds (this procedure discards the particles above 30micron).
- Decant supernatant into another labelled test-tube and add distilled water.
- Spin the decanted supernatant at 850 rpm for 1 minute
- Discard supernatant containing particles greater than 2 microns.
- Re-suspend the settled sediments using distilled water and repeat the process immediately as above until the supernatant is clear.
- Dilute the settled sediments then spray on to a slide.
- Dry the slide on a hot plate.
- Affix the coverslip using an optical mounting medium (Norland Optical Adhesive 61.)