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Pegmatites are dike-like bodies of large grained igneous rock, formed by the slow crystallization of highly volatile solutions, during the last phase of solidifying deep-seated granite magmas. The name comes from the Greek word “pegmos” meaning “coarse”, and refers to their large-sized crystals, which are mainly feldspar, quartz and mica.  Their origin begins when a huge mass of molten magma intrudes upwards through cooler surrounding country rock, a name given to all other rocks, which are not part of those under discussion. As the hot magma comes into contact with the country rock, cracking occurs, and chunks of wall rock fall into the magma chamber, dissolving and adding new mineral-making materials to the mixture. Chunks of undissolved rock will remain as xenoliths, or foreign rock when the magma hardens. When the main granite mass begins to solidify it shrinks with cooling, forming spaces between it and the upper wall rock where residual superheated solutions rich in water, fluorine, boron and phosphorus can escape into. These volatile solutions widen the cracks by further dissolving of the country rock, and form outward -projecting pegmatites, and, because of their volatile components, cool down very slowly, and form a rock of large crystal size.  Sometimes individual crystals can be very large, and giant crystals of feldspar, quartz, mica, spodumene, and beryl are found in several places.  A colossal 2 000 ton feldspar crystal was once quarried in Karelia, in Russia!  Most crystals are much smaller and form a compact rock where the best crystals are those which have grown unhindered in open hollows called miarolitic cavities. The main minerals of pegmatites are the granite suite. Microcline is the common feldspar with lesser amounts of orthoclase and albite. Both muscovite and biotite mica can be present.  The quartz is crystalline and can range from colourless to milky, smoky and rose coloured hues. Sometimes both quartz and feldspar crystallize together, forming a rock with a striking surface pattern that looks like a kind of ancient runic writing, and which is called graphic granite.  Besides the granite minerals, pegmatites can produce whole suites of other exciting minerals of great interest to collectors, and at times in sufficient quantity to make pegmatites a rich source of rare metals and gemstones.  The volatile substances produce interesting minerals like topaz, fluorite, tourmaline, apatite, and other phosphates.  Among the rarer metals can be listed minerals containing tin, tungsten, beryllium, lithium, bismuth, niobium, tantalum, and radio-active elements.  Sometimes whole related mineral families can be present, producing lithium pegmatites, as at Bikita in Zimbabwe, or phosphate pegmatites like Sandamap in Namibia.  All of which make pegmatites a favourite source of mineral specimens.  They are also famous for their gemstones, and to name a few there are the quartz crystalline gems, topaz, tourmaline, the beryl gemstones, kunzite, amazonite, zircon and spessartite garnet.  Nor has the list of pegmatite minerals ended here. For in and around pegmatites there are a number of accessory minerals, some formed in the margins by dissolved country rock like garnet and epidote, and others by the alteration of existing pegmatite minerals.  Hence clove-brown lithiophylite can alter into attractive purple purpurite.  There are such an exciting variety of pegmatite minerals that one could collect these by themselves, and not worry about other minerals at all.  Also, learning about how these minerals are formed and what other associated species can be found with them, makes collecting pegmatite minerals a never-ending learning adventure.  TVJ