aware of the state of the tides in the area. Never take chances by climbing high cliffs of crumbling rock or clay (many have died attempting it). Dried up natural lake beds and caves in the form of pitfall traps frequently also have high concentrations of fossils (e.g., Cuddie Springs and Naracoorte Caves in Australia). Generally in appearance, a fossil will be either a different colour to the surrounding rock, because of the different mineral content, will have a defining shape and texture or a combination of both. A fossil can also be extracted from its geological environment, having similar characteristics in colour naturally embed from the sedimentary formation (surrounding rock) it was found within. Collecting techniques The techniques used to collect fossils vary depending on the sediment or rock in which the fossils are to be found. For collecting in rock a geological hammer, a variety of cold chisels and a mallet are used to split and break rocks to reveal fossils. Since the rock is deposited in layers, these layers may be split apart to reveal fossils. For soft sediments and unconsolidated deposits, such as sands, silts, and clays, a spade, flat-bladed trowel, and stiff brushes are used. Sieves in a variety of mesh sizes are used to separate fossils from sands and gravels. Sieving is a rougher technique for collecting fossils and can destroy fragile ones. Sometimes, water is run through a sieve to help remove silt and sand. This technique is called wet sieving Fossils tend to be very fragile and are generally not extracted entirely from the surrounding rock (the matrix) in the field. Cloth, cotton, small boxes and aluminum foil are frequently used to protect fossils being transported. Occasionally, large fragile specimens may need to be protected and supported using a jacket of plaster before their removal from the rock. If a fossil is to be left in situ, a cast may be produced, using plaster of paris or latex. While not preserving every detail, such a cast is inexpensive, easier to transport, causes less damage to the environment, and leaves the fossil in place for others. Fossilized tracks are frequently documented with casts. Subtle fossils which are preserved solely as impressions in sandy layers, such as the Ediacaran fossils, are also usually documented by means of a cast, which shows detail more clearly than the rock itself. Preparation and cleaning Sometimes, for smaller