There are many slide preparations that you can do with beginning microscopes. One of these is smear slide. A smear slide is composed of a thin layer of unconsolidated sediment fixed on a glass slide for petrographic microscopic examination. They are a powerful method for quickly evaluating tiny quantities of sediment like mineralogy, provenance, form, size as the basis for sediment classification. It is also useful for determining the incidence of microfossils. Smear slides also grants surprisingly accurate percentage data that are useful for recognizing trends in cored sequences. As part of the routine examination and description of cores and from any anomalous layers, samples for smear slides should be taken at regular intervals. They can also be utilized to examine treated sediment in determining the effectiveness of the procedures being used.

To start preparing for smear slides, first label a standard glass slide with information about the sediment sample. Information included should be the core code, sample depth in cm from the top of the core, reason for slide, color, and any special treatment. When choosing label materials it is important to remember that adhesive properties may be lost after some time. Standard marking pens also wipe off easily. The best thing to do to permanently label the slide is by using a diamond tipped pencil to scratch the label on the end of the slide.

The hot plate is then turned to the lowest setting, or slide warmer to medium heat. The mounting medium is placed upside-down in a 100-mL beaker on the hot plate, sending the bubbles to the bottom of the bottle and making the cement less viscous. The slide is cleaned by wiping with water or alcohol on a lint-free tissue. It is imperative to remove any glass shards as these may be mistaken for volcanic ash when viewed under the microscope. A very small amount of sediment is placed on the slide since individual components will be indistinguishable under the microscope if the sample is too crowded.

A drop or two of deionized water or alcohol is added to the slide because it is easier to add the liquid before the sediment. Water is chosen when the sediment is high in organics, since alcohol will dehydrate organic matter. Otherwise, alcohol is used if the sediment contains evaporites or other highly soluble minerals. Sediment is disperses and spread on the slide using a toothpick, tiny spatula, or glass rod. Fresh, wet sediment works best. Dry sediment should be moistened and softened before it can be smeared. It is also a good idea to break up lumps since there is the danger of damaging any microfossils. Make a uniform, thin coating approximately the same size as the cover slip. Ideally grains will be essentially in a single layer and close together. Clumpy organics will make a more thin slide than fine clays and silts, given the same volume of material.

The slide is then placed on the slide warmer or hot-plate and allowed to dry for about 2-5 minutes. The slide must be totally dry before adding the optical cement. The cement is not miscible with water. The cement will form blobs and crazed patterns instead of a uniform, isotropic sheet if the sediment is still wet. Drip 2-3 drops of mounting medium onto the cover glass. To avoid contaminating the mounting medium, never touch the dropper to the slide. Bubbles are almost unavoidable in the first slide made after removing the cap from the bottle, but should be minimal afterwards. It is best to wait until several slides are ready for medium and mounting them all in sequence before recapping the bottle. Sand-sized grains produce more void space between the slide and the cover slipthan organics and silt/clay-sized grains. Use 4-5 or more drops of Norland. The cover slip is carefully placed on the slide. If you have coarse-grained sediment you need to utilize more mounting medium to fill up the space between the slide and cover-slip. Finally, place the slide under ultraviolet light to cure for 1-2 minutes.