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Fossil Collecting/Equipment

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It is important to have the right kind of field equipment when looking for fossils, and safety should always be an important concern. A hard hat is essential to protect you from loose stones that may be dislodged from cliffs above, but remember that this will not protect you from larger falling rocks. Hard hats are normally a requirement in operational quarries.

Safety goggles and protective gloves are also essential. Rocks can be sharp and dangerous, safety goggles will protect your eyes from chips while hammering, and gloves will protect your hands.

You should always dress appropriately for collecting trips, taking into account the climate and terrain of the area. Sturdy footwear, such as walking or hiking boots with steel toes, are usually a must. In general, wear old clothes because you will almost certainly get dirty and/or wet. A hand-lens is also important as it will enable you to recognize fine details in both the rocks and fossils they contain. A hammer, chisel and wrapping materials are the basic equipment required for fossil collecting, along with a stout rucksack or canvas bag for carrying your equipment and your fossil finds.

Remember that the steel of many ordinary hammers is too soft for use on most type of rock. The steel may splinter and the flying fragments may cause injury, not only to the person using the hammer, but to his or her companions as well. Always strike with the hammer away from the body. The head of a geological hammer or rock pick is made from specially hardened steel designed for use on rocks. The head is either firmly attached to a wooden shaft, or the hammer have the head and the shaft formed from one piece of steel. The head has a square face at one end, while the other end either tapers to a point of has a straight chisel edge. The point of such picks are not meant for striking rock directly, but for tapping rock (such as shale) open along planes and for prying. The hammer end is meant for striking. In dry climates shrinkage can be a problem with hammers which have a wooden shaft, the wood may shrink so that the head becomes loose. If you do not have a wedge to force into the wooden shaft, soaking the head of the hammer in water will swell the wood and should keep the head on the handle.

A convenient weight for a general purpose geological hammer or rock pick is around 1 kg (2 to 3 pounds). For breaking very hard rocks one may need a hammer of between 3 and 6.5 kg (7 and 14 pounds) in weight, with a correspondingly longer and thicker shaft. A hammer that is too heavy is tiring to use and results in unsafe work.

For extracting fossils from harder rocks, a sturdy mallet and cold steel chisels may also be required. Usually one needs a range of chisels in size from small ones with a sharp edge of about 1 cm (quarter of an inch), to much larger and heavier chisels. A broad-bladed chisel is often very useful for splitting rocks along their bedding plane.

Knowing the type of rocks on which one will be working is useful so that one can select the appropriate tools and not have to carry any unnecessary weight.

Different types of rocks will break differently and a beginner should put in a little practice, getting the feel for a particular type of rock before he or she starts hammering out fossils. It is all too easy to ruin a specimen with one ill-placed blow of a hammer.

Extracting a specimen that is embedded in solid rock may prove to be a long and difficult process. Before attempting to extract a specimen, the collector should make sure that it is feasible to remove it without destroying or damaging it. Be sure to leave sufficient rock beneath the specimen to protect it from fracturing; excess matrix can always be trimmed once you get the specimen home.

For soft sediments and unconsolidated deposits, such as sands, silts and clays, a spade and a flat-bladed trowel or stout bladed knife may be the most useful tools for clearing the area around a fossil. Brushes are also useful for removing loose sediment from around fossils. Also, a word of caution: whenever grinding or chipping rock beware that the rock dust created can be very harmful to the lungs. Always take appropriate measures, such as using a mask or respirator, when doing anything with rocks that create dust.

Use a sieve to separate fossils from sands and gravels. Usually a smaller mesh is required in order to avoid losing small fossils. One practical difficulty with using sieves in the field is that they easily become clogged, especially when the material sieved has a high moisture content. However, under dry weather conditions the more durable fossils, such as teeth and bones, can be quickly and easily sieved out of loose sands. Remember that shaking the sieve is always liable to damage or destroy fragile fossils.

If there is water available, such as on a beach or next to a stream, the material containing the fossils can be sieved wet and the matrix gradually washed away. Wet sieving is a technique that is frequently used for the collection of small mammalian fossils, and by using this technique even the smallest specimens may be recovered. Any fossils you will thus obtain create a more balanced representation of the fossils present at that particular locality. Alternatively a block of matrix with the fossils inside may be dug out and taken home for treatment indoors. To do this use a flat-bladed trowel, or stout bladed knife, and simply carve away the surrounding sediment. Once free, carefully wrap the matrix block containing the specimen before taking it home.

Before setting out on an expedition, ask other collectors who are familiar with the area where you intend to collect exactly what tools are needed.