- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
A technique for examining foraminifera in rock slices has the advantage that it provides the third dimension which is lacking in thin sections. Orientated sections of individual foraminifera are produced by paring down the specimen with a surgical scalpel to its axial or sagittal plane of section, which, for convenient working, should lie with 45 degrees of the surface of the slice. The position of each cut can be checked by irrigating the specimen with clove oil, and it is possible to adjust the angle of the cut as the specimen becomes increasingly exposed. The successive series of sections observed in this way provides a clear impression of the test's internal organisation, and provides an excellent opportunity to relate random two-dimensional sections to the complete structure. Thin sections are prepared by coring the selected specimen from the limestone by means of a small diamond-impregnated hollow bit.