Instant peels made of marine polyester resin are a quick, easy and inexpensive method of obtaining undisturbed samples of sediments. They permit stereomicroscope measurements to be taken of minor sedimentary structures, textures, and fabrics. Peels can be X-rayed to study sedimentary structures or treated and used to prepare thin sections. The technique can also be used to study bottom distributions and orientations of shells. Limitations of the technique are related to the taking of the peel itself. To obtain a reasonably good sample, the surface to be sampled must be nearly flat; it must not contain anomalously large particles mixed with finer particles; it cannot be wet, and it must be at a temperature not much lower than 60 degrees F (15 degrees C). If these conditions are not fulfilled, either the resin will not solidify properly, or the peel will selectively pick up different grain sizes. Some of these difficulties can be overcome by selecting resins that polymerize at low temperatures or are soluble in water.