The present volume "Rare Earth Elements" A 6b deseribes in its first part the origin, mode of oeeurrenee, and behavior of Y and/or RE elements in the hydrosphere and atmosphere. Separately for marine and non-marine environments (surfaee, subsurfaee, mineral, and thermal waters), the behavior of RE (ineluding Y) in the hydrosphere eomprises espeeially the relationship between eontentleomposition and the ehemistry of water, and the processes aeting during migration, removal, and preeipitation are outlined; the influenee of biologieal material is mentioned. Behavior of RE in the atmosphere involves mainly transport, regional differenees, and temporal variations as weil as removal by preeipitation; the anthropogenie influenee is only outlined.

The seeond part of this volume treats, partly in a more summary manner, the eosmoand geoehemieal eyeles and the balance of Y and/or RE elements. The relationship between geodynamie position and type of magmatism, as weil as the geoehemieal variations in the geospheres, especially mantle and erust of the earth, are deseribed in greater detail.

There has been gold production in Kazakhstan since the ancient times, the earliest primary gold workings having been dated to the Bronze Age (2000-4000 BC). Ancient workings, otherwise called "Chudskie" pits that often contain implements dating to the Stone or Bronze Age, still survive to the present at many gold deposits in the north and east of the country.

Gold production in Kazakhstan resumed only at the beginning of the 18th century, with the first gold produced in 1725 at the Kolyvano-Voskresensky plant in Russia having been recovered from Kazakhstan's pyrite-polymetallic gold-silver deposits at Rudnoi Altai. More than 191 of by-product gold were mined here between 1745 and 1800. Gold production at these properties had increased steadily in the 19th and 20th centuries, and has accounted for 30-40% of the country's total output in recent years.

The distribution of gold in the lithosphere bears critically on models for gold ore deposits. One group of workers advocates derivation of gold from large masses of rock through fluid-rock reactions in the deep crust (Kerrich, 1983; Groves and Phillips, 1987; Colvine et at., 1988) while others stress the importance of relatively restricted petrogenetic groups of rocks termed source rocks that concentrate gold above the norm (Viljoen et al., 1970; Keays, 1984). It is therefore important to know the average gold contents for rock types of the lithosphere, and what concentrations are potentially indicative of mineralization. Tilling et at. (1973) noted that unaltered igneous rocks generally have less than 5 parts per billion (ppb) gold and that 10 ppb is exceeded only rarely. A survey of more recent data presented here confirms that statement. As ore deposits may concentrate gold 104 times the rock background, gold contents of only a few tens of ppb may indicate ore-forming processes.

Gold, a chemical element with the symbol Au, is a highly sought-after precious metal, having been used as money, in jewelry, in sculpture, and for ornamentation since the beginning of recorded history. The metal occurs as nuggets or grains in rocks, in veins and in alluvial deposits. Gold mining consists of the processes and techniques employed in the removal of gold from the ground. There are several techniques by which gold may be extracted from the Earth. Since the 1880s, South Africa has been the source for a large proportion of the world’s gold supply, with about 50% of all gold ever produced having come from South Africa. Other major producers are the United States, Australia, China, Russia and Peru. The world's oceans also hold a vast amount of gold, but in very low concentrations. At current consumption rates, the supply of gold is believed to last 45 years. This book will present current research on gold mining including methodologies for discovering new deposits of gold as well as economic and environmental issues. <...>