Minerals, Rocks and Fossils [antikvár]

I ll iMl/ l«/ Introduction This field guide is divided into three sections, namely minerals, rocks (including meteorites and tektites) and fossils. Each section comprises an introductory part, which is illustrated by line drawings, and a descriptive part, which is illustrated by line drawings and colour photographs. The introductory sections include the minimum basic information required to follow the descriptive sections adequately, while the descriptive sections, for ease of reference, are always arranged so that photographs and accompanying text are opposite one another. To make.the best use of the book the contents page and index should be used freely. The contents list will enable you to turn quickly to the appropriate section of the book, whereas if a tentative identification has been made, then reference to the index will immediately direct you to the relevant page. The index includes not only the names of specific minerals, rocks and fossils, but also technical terms which are used in describing them. By consulting the index you will be referred to the page on which the term is defined, and possibly illustrated. The stratigraphical column is given on page 310, and will be a particularly valuable reference for collectors of fossils. How to collect The basic equipment required is a hammer, chisel, notebook and pencil, felt-tipped pen, wrapping materials and a bag. The usual geological hammer has a square head and a chisel edge, which is particularly useful for splitting rocks when looking for fossils. Do not be tempted to use any other kind of hammer. Geological hammers are specially tempered and others are likely to splinter when hammering, and metal splinters could damage the eyes. A steel chisel is sometimes required to prize open rocks which resist hammering, or for carefully breaking specimens which might be damaged by blows from a hammer. When hammering be very careful Indeed of flying splinters of rock. Protective goggles can be obtained. Specimens should be carefully numbered: use either a felt-tipped pen or sticky tape on which a number can be written. The exact locality from which the specimens were collected should be recorded in the notebook. Specimens should always be wrapped in plenty of newspaper in order to prevent chipping or scratching, and small or delicate specimens are best carried in a small box, such as a match or cigar box. If a large collection is to be made, or If long distances are to be walked, then a stout rucksack is the most suitable kind of bag to have. The best places to collect minerals, rocks and fossils are usually quarries, cliffs, road cuttings and mine dumps, but any outcrop of rock may prove fruitful. Particular care Is needed, however, when collecting near quarry faces or from the foot of cliffs, and permission must always be sought if it Is intended to collect from outcrops on private land. Remember to take care and precautions if you intend to do field work on your own, and always tell someone of your Intended route before setting out. Geological maps, sometimes on a large scale, are