This is a photomicrograph of a mineral section that had been prepared by a member of the Postal Microscopical Society (PMS), which is based in England. A mineral section is prepared by cutting a thin slab from a larger mineral sample with a very thin circular diamond saw. The slab is then attached to a glass slide and wet ground with finer and finer abrasives to a thickness of 0.025". It is then very carefully transferred to a microscope slide, a drop of Canada balsam is applied and a cover glass is placed on top. This forms a seal and gives a clear view of the specimen. Very fortunately, this particular section happened to be cut right to the center of a single foraminiferan, thus revealing its spiral structure. Incidentally, the evaluation of the species and number of forams in a mineral section is one of the important tools in determining the probability of the presence of petroleum deposits, this method having been used for many decades.
Regards,
George
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