,this etext was produced by ,justin 7dopefishjustinyahoo4com74 ,,contents ,,collecting ,,seashells ,,seashells4 4 4,,what ,,are ,,they8 ,,the ,,shell ,,as ,,an ,,architect ,,let',s ,,meet ,,some ,,shells ,,where ,,to ,,look ,,starting ,a ,,collection4 4 4,,here',s ,,how ,,collecting ,,rocks ,,rocks ,,are ,,made ,,of ,,minerals ,,main ,,kinds ,,of ,,rocks ,,collecting ,,gems ,,for ,,the ,,lucky ,,few ,,introduction ,millions of people throughout the world have found many hours of pleasure1 adventure and education by collecting either rocks or shells4 ,this booklet won't tell you everything there is to know about rocks and shells4 ,that would require many large volumes4 ,we only want to arouse your curiosity about two delightful pastimes that are so broad and varied that they can lead to a career or a satisfying hobby4 ,shell ,oil ,company's interest in the subjects comes from its history and the nature of its business4 ,the name--chosen by a company that was founded years before anyone thought of drilling for oil--comes from the seashells this company brought from the ,orient for use in mother-of-pearl items such as buttons and knife handles4 ,now its world-famous emblem 7the ,pecten7 is recognized by millions of people in every walk of life4 ,it's on service stations1 trucks1 buildings1 oil derricks and chemical plants4 ,even the company's industrial lubricants are named for shells because shells have the same scientific names everywhere in the world4 ,for an oil company1 rocks have a special interest4 ,crude oil is found not in underground lakes or pools but in the tiny spaces between grains of sand or in the pores of rocks4 ,only certain types of rock formations are favorable to the accumulation of oil4 ,thus1 oilmen need to know everything they can about the right kind of rocks4 ,shell has scientists who work with rocks all day and laboratories filled with rock1 mineral and crystal specimens4 ,we are always learning new things about them4 ,the pages that follow provide basic information about two subjects that can be richly rewarding whether you follow them for profit1 as ,shell does1 or for pleasure1 as millions of people around the world do4 ,,seashells4 4 4,,what ,,are ,,they8 ,first1 a seashell is one of the #ajj1jjj species of backboneless animals belonging to the zoological group known as the ,mollusca4 ,mollusks include not only the familiar clams1 scallops and snails1 but also the squids1 octopus and ,chambered ,nautilus4 ,other shells found in the ocean include those of crabs1 lobsters1 barnacles and sea urchins4 ,true molluscan shells come in two main varieties3 ,,bivalves and ,,univalves4 ,bivalves have two valves1 fitting together along a toothed hinge on one side1 and kept closed by means of ,,adductor ,,muscles4 ,univalves have only one shell1 usually coiled1 but sometimes shaped like a cap or miniature volcano4 ,some marine univalves can seal themselves inside with an operculum1 which covers the open end of the shell like a trap door4 ,although shells take on many different shapes1 they are much alike inside4 ,each has a foot1 a breathing siphon1 a tiny brain and heart1 and a fleshy mantle which secretes lime for shell-building4 ,most true mollusks have eyes1 but a few are blind4 ,many have teeth1 called ,,radulae4 ,like any other animal1 the mollusk generally moves about4 ,it pushes along on the ocean floor on its foot1 or it might swim a little4 ,it lays millions of eggs and hatches countless baby mollusks4 ,it lives its life in its shell1 lugging it around1 snuggling into it when alarmed1 burrowing into mud1 fastening itself to a rock and creating ingenious camouflage4 ,it builds its calcareous house with a great instinctive talent for color and sculpture4 4 4and the closer it lives to the tropical zones1 the more beautifully spectacular is its art4 ,the two parts of a bivalve shell are like thin saucers1 concave inside1 convex outside4 ,the inside is smooth1 polished4 ,the outside is rougher1 sometimes with graceful ribs or concentric ridges or combinations of both4 ,univalves are conical and spiraling1 with a series of whorls coming down like widening steps from the tiny nucleus on top4 ,univalves may have spines on their shoulders4 ,the opening1 called the aperture1 has a delicate right-hand rim called the lip and a heavy1 left-hand edge called the columella4 figure captions ,,bivalve',s anatomy3 a7 foot1 b7 adductor muscles1 c7 gills1 d7 hinge1 e7 adductor muscles1 f7 siphon1 g7 stomach1 h7 mantle4 ,oysters1 clams1 mussels all have them4 ,,univalve',s anatomy3 ,as before1 a7 foot1 b7 siphon1 c7 mantle1 but also d7 operculum4 ,univalves include whelks1 winkles1 conchs4 ,chambered nautilus is brother to the octopus1 but he wears his castle permanently--and on the outside4 ,,the ,,shell ,,as ,,an ,,architect4 4 4,,how ,,does ,,he ,,do ,,it8 ,picture a vast undersea factory with billions of shells in constant production4 ,each is made slowly and entirely of lime which the little animal inside extracts from its food1 almost from the first day of its life4 ,each shell builder flawlessly follows the shape and design of the species to which it belongs4 ,all these sea animals come from eggs1 all different according to species1 but all laid in measureless abundance--sometimes released into the open sea1 sometimes protected in homemade nests1 sometimes encased in capsules strung like beads4 ,hatched1 most baby mollusks swim freely for a while1 their tiny1 transparent bodies almost invisible to the naked eye4 ,then they start building a heavier shell and sink to the bottom4 ,each shell's mantle contains a network of microscopic tubes4 ,each tube secretes a tiny amount of lime which instantly adheres to the shell4 ,the animal builds his shell to the proper size and thickness and determines its ridges and whorls4 ,some kinds of shells take two to five years to reach maturity4 ,others keep growing all their lives4 ,color tubes are spaced like holes on a player piano roll allowing pigments to tint the shell at the right spots in the growing design4 ,many shells are covered with a self-made brown sheath1 the ,,periostracum4 figure captions ,most shells don't change basic structure as they grow4 ,young ,,cowries 7l471 however1 alter greatly in maturity 7r474 ,tough1 lozenge-shaped egg cases on this string hatch baby ,,whelks like ones shown4 ,newborn mollusks are usually free swimming1 moved by hairs4 ,shell is there1 but transparent for a few days4 ,,let',s ,,meet ,,some ,,shells ,latin abounds in conchology1 as you've already noticed4 ,why8 ,well1 because this is a hobby and science that spans the world4 ,englishmen1 ,frenchmen1 ,greeks and ,indians all have their own local names for shells4 ,but scientists everywhere give things in nature ,latin names4 ,shells of the same sort carry the same ,latin label on every beach in every sea4 ,much of the fascination of shell collecting is learning these names and how they were derived4 4 4 for shells have been named for almost everything4 ,we can't catalog #ajj1jjj species here1 but let's call off the names of a few of the interesting specimens you might come across4 ,many shells have wonderfully descriptive names4 ,for example1 there's ,,arca ,,zebra1 which has stripes and looks like a miniature turkey wing and is commonly called ,turkey ,wing4 ,then there's a scallop called the ,lion's ,paw2 ,,nerita ,,peloronta1 or ,bleeding ,tooth2 and ,,cypraea ,,cervinetta1 little deer cowrie which resembles a spotted fawn4 7,cowrie is a common name for a kind of shell used as money in parts of ,africa and ,asia47 ,there are shells named for people3 ,,conus ,,juliae 7,julia's cone shell71 ,,pleurotomella ,,jeffreysii 7,jeffrey's ,pleurotomella71 and ,,aclis ,,walleri 7,waller's ,aclis74 ,many are named for the place they were first discovered3 ,,urosalpinx ,,tampaensis1 ,tampa ,drill2 and ,,iphigenia ,,brasiliana1 ,brazil ,clam4 ,some shells take their names from flowers3 ,,fasciolaria ,,tulipa1 ,tulip ,shell4 ,many get named from mammals--not always too accurately4 ,,cypraea ,,tigris and ,,cypraea ,,zebra both have spots1 not stripes4 ,but ,,cypraea ,,talpa 7mole cowrie7 does look a lot like a mole4 ,then there's 7let's skip the ,latin this time7 ,magpie ,shell1 ,mottled ,dove ,shell1 ,mouse ,cone1 ,horse ,conch1 ,checkered ,pheasant1 and ,cuban ,frog ,shell4 ,there's mythology3 ,venus1 ,neptunea1 ,pandora1 ,tritonis4 ,music3 ,buccinum 7trumpet71 ,citharas 7guitar71 ,harpa4 ,religion is represented1 too4 ,in the genus ,,mitra are species ,,pontificalis1 ,,episcopalis1 ,,papalis1 and ,,patriarchalis4 ,some other fanciful names are3 ,great ,heart1 ,jewel1 ,box1 ,rising ,sun1 ,checkerboard1 ,wood ,louse1 ,writhing ,shell1 ,sundial1 ,key-,hole ,limpet1 ,red ,turban1 and ,black ,lace ,murex4 ,and that's where we stop and draw breath4 ,you'll find others--there are literally thousands more6 ,you've got to be a detective4 ,these little animals are the natural food for many of the larger undersea creatures1 so one of their greatest talents is hiding4 ,approaching danger1 whether from octopus1 fish or man1 arouses caution in a small mollusk and it becomes as inconspicuous as it can4 ,this can be pretty inconspicuous1 as the novice conchologist learns early in his search4 ,,remember - by all means1 don't be a landlubber4 ,get into the water4 ,no matter whether you go shelling up ,north1 down ,south1 in the ,west or in the ,tropics1 you won't get any satisfaction 7or value7 from collecting dead shells washed up on a beach4 ,to build a good collection1 you should take your mollusks alive1 then clean and prepare them yourself4 7,more about that later47 ,you won't find live ones unless you go where they live4 figure captions ,,conus ,,spurius ,,alphabet ,,cone ,,cyrtopleura ,,costata ,,angel ,,wing ,,terebradislocata ,,atlantic ,,auger ,,murex ,,dilectus ,,lace ,,murex ,,epitonium ,,humphreysi ,,humphrey',s ,,wentletrap ,,lyropecten ,,nodosus ,,lion',s ,,paw ,,fasciolaria ,,distans ,,banded ,,tulip ,,diodora ,,cayenensis ,,keyhole ,,limpet ,,anatina ,,plicatella ,,channeled ,,duck ,,where ,,to ,,look99 ,many shells are endowed with perfect camouflage4 ,the colorful seafans off ,florida are hiding places for the ,,simnia whose long purple or yellow shells1 clinging to sea fans and matching perfectly in color1 are nearly indiscernible4 ,other shells create disguises as they go along4 ,in ,florida waters1 a pile of dead and broken shells may be worth investigation3 ,,xenophora ,,conchyliophora 7carrier shell7 might be under it2 it cements the old1 discarded shells to its own4 ,northern tide pools accommodate many kinds of ,,littorina 7periwinkles74 ,these pretty little shells1 in shades from yellow to brown1 are well concealed among the dimly-lit seaweed4 ,along any rocky shore1 limpets grow as wide as two inches but remain hard to find4 ,their turtleback shells1 covered with moss1 look just like rocks1 and they stick so tightly to the big stones that--even when they are seen--they can scarcely be pried loose4 ,abundant on wave-washed beaches of both the ,north and the ,south are dead shells of another perfectly camouflaged clam called ,,arca4 ,while alive1 the shells are covered with hairy1 brown or black epidermis and look like pebbles among tufts of seaweed and marine grass4 ,on the ,west ,coast1 the abalone is a most typical species in addition to being a delicious food4 ,the bright-hued shell is widely used for souvenirs such as ash trays and is in demand for buttons and decorative purposes4 ,most shells of interest to the collector are found in the sea-- but not all4 ,living forest mollusks have been found #ah1jjj feet high in the ,himalayas4 ,and in this country a great variety of mollusks live in rivers1 ponds1 and even hot springs4 ,several species are peculiar to the ,nile ,river4 ,also1 species of mollusks live on land--for example the common garden snail4 ,wherever you go1 be it the ,south ,seas1 a mountain lake1 or the shoals off the ,gulf ,coast1 you'll find shells to collect and opportunities to expand your hobby4 99,collectors should familiarize themselves with local regulations4 ,in some areas1 such as parks and marine sanctuaries1 collection of shells and other marine organisms may be restricted or prohibited4 ,,starting ,a ,,collection4 4 4,,here',s ,,how ,knowing ,,where to look for shells you probably wonder ,,when is the best time4 ,the answer is ,,anytime4 ,mollusks know no season4 ,some species appear suddenly for several days and then vanish2 others can be found almost anytime4 ,most mollusks appear at night1 but others work only in the daytime and go out of sight after dark4 ,the tides may have something to do with it4 ,so does the weather-- it can be hot or cold1 dry or rainy4 ,while you won't find the same shell at all times1 you'll find a great variety at any time4 ,what to take8 ,the things pictured on page #h should be enough4 ,if you're going out on the coral reefs along ,florida1 it would be wise to keep your legs covered as protection against stings or scratches4 ,don't ever forget to wear some kind of shoes in the water4 ,even though you're wearing a mask or goggles1 take along a gig or some slender stick and feel your way along so you don't fall into a hole you can't see in the deceptive near-tropical waters4 ,if1 despite precautions1 you get a sea urchin's needlelike spine broken off in your skin1 soak the wound in vinegar which will dissolve the fragments and stop the pain in a few minutes4 ,tiny shells buried in sand can be netted in your sieve4 ,clinging ones must be chiseled off rocks4 ,frail1 delicate clingers should be gently nudged loose with tweezers4 ,submerged sandbars are good spots to find several kinds of univalves and bivalves1 but the latter will dig themselves quickly out of sight--as far down as several feet4 ,when you see one going underground1 don't dig directly over it--you might break its shell4 ,instead1 dig to one side1 and break the mud or sand away with your hands4 ,after you've had a good day's haul and a rest 7you'll need one7 you must clean your shells4 ,put your tiniest1 most fragile ones in rubbing alcohol4 ,put the rest in a pot of fresh water and slowly bring it to a boil4 ,let them cool in the water slowly to prevent the glossy shells from cracking4 ,when cool1 your bivalves will be gaping open2 simply scrape them clean4 ,your univalves will be more difficult2 remove the animal with a crocket hook or other piece of bent wire1 turning it gently with the spiral2 try to get it out whole to save yourself trouble4 ,save the univalve's operculum and slice it off the muscle that holds it4 ,it will preserve indefinitely and is a valuable part of the shell4 ,clean the shell's exterior by scraping it gently with a dull knife or nail file1 then soaking it in a ,clorox solution 7#a cup to #b quarts water7 for two hours4 ,some will be covered with an ugly skin--scientists keep this intact and you should try to4 ,the best collection has two of each species--one with and one without the epidermis4 ,after your clean shells have dried 7in shade1 not sun71 go over them with a rag dampened in light oil4 ,this insures preservation and restores their natural luster4 ,every three months or so1 rub them with oil again--their most delicate colors will remain brilliant for years4 ,don't ever use shellac1 lacquer or varnish4 ,get a reference book from your library and identify your shells4 ,keep an account of when and where you collected them4 ,store your shells in closed containers to protect them from sunlight and dust4 ,almost any set of small drawers or a cabinet will do4 ,matchboxes or pillboxes are excellent for small specimens4 ,for display purposes1 glass-covered cases are best to prevent handling of the shells4 ,a shell's beauty is often deceptive4 ,many unattractive and drab shells are worth hundreds of dollars while the most colorful are frequently valued at a dollar or less4 ,the rarity of a species determines its value4 ,a truly valuable shell may come from deep1 inaccessible waters or remote lands--or it may be one of an extinct species4 ,a ,slit ,shell collected #ajj fathoms down in waters off the ,british ,west ,indies is valued at #ajjj4 ,another undersea treasure1 the ,glory-,of-,the-,seas1 was first found in #agga and one time would bring the conchologist #aejj4 ,the greatest rarities1 however1 are truly valueless and are not for sale4 4 4 4,and there it is1 the fascinating hobby of shell collecting4 ,it's a lot of work--but a lot of fun1 too4 figure captions ,take a ,,sieve4 ,or an orange sack4 ,besides carrying your shells1 it may help you catch them4 ,a few pint ,,bottles will hold delicate ones4 ,,mask 7or goggles7 is essential for looking underwater4 ,bathing suit or old clothes1 of course4 ,high shoes 7or sneakers7--never go barefooted6 ,heavy cloth ,,gloves4 ,watch out for sunburn6 ,,gig or fish spear 7if you're going ,south7 to keep pesky crabs1 sea urchins off4 ,,clam ,,digging ,,hoe or trowel for burrowing shells4 ,,vinegar for first aid1 in case you're stuck by urchin's spines4 ,,chisel and ,,hammer to get the clingers1 spatula for frail limpets4 ,you may find other hardware handy1 but these are basic4 ,,now ,,let',s ,,look ,,at ,,rocks ,,rocks ,,are ,,made ,,of ,,minerals ,rocks1 to begin with1 are made of minerals4 ,what is a mineral8 ,the definition may sound difficult--a mineral is a chemical element or compound 7combination of elements7 occurring naturally as the result of inorganic processes4 ,but don't be discouraged4 ,things will clear up soon4 ,the world contains more than #a1ajj kinds of minerals4 ,these can be grouped in three general classes4 #a4 ,,metallic ,,minerals4 ,these include things most of us would think of if we were asked to name some minerals4 ,familiar examples are copper1 silver1 mercury1 iron1 nickel and cobalt4 ,most of them are found in combination with other things--as ores4 ,we get lead from galena1 or lead sulfide4 ,tin comes from the ore cassiterite2 zinc from sphalerite and zincblende1 or blackjack4 ,chromium that makes the family car flashy comes from chromite4 ,many minerals yield aluminum4 ,uranium occurs in about #ej minerals1 nearly all rare4 ,twenty-four carat gold is a metallic mineral4 ,a #ad carat gold ring contains #ad_/bd or #eh gold4 ,an average sample of earth contains #i aluminum1 #e4e iron1 4#ja zinc1 4#jjh copper1 4#jjd tin1 4#jjb lead1 4#jjje uranium1 and 4#jjjjjjf gold or platinum4 ,it would be hopelessly expensive to recover such metals from an average ton of earth4 ,that's why metallic minerals are taken from concentrated deposits in mines4 ,many valuable minerals are found in veins running through rock4 ,veins can be formed when3 7a7 mineral-laden ground water seeps into cracks1 evaporates1 and leaves mineral grains that build up into a vein2 7b7 hot water from deep within the earth fills cracks1 then cools and deposits much of the material in solution as minerals in a vein--sometimes including metals such as gold and silver2 7c7 molten gaseous material squeezes into cracks near the earth's surface1 then slowly hardens into a vein4 #b4 ,,nonmetallic ,,minerals4 ,these are of great importance to certain industries4 ,you will find them in insulation and filters4 ,they are used extensively in the ceramic and chemical industries4 ,they include sulfur1 graphite 7the lead in pencils71 gypsum1 halite 7rock salt71 borax1 talc1 asbestos and quartz4 ,undoubtedly1 you'll have some nonmetallic minerals in your collection4 ,rocks containing asbestos are especially handsome and varied4 #c4 ,,rock-,,forming ,,minerals4 ,these are the building materials of the earth4 ,they make mountains and valleys4 ,they furnish the ingredients of soil and the salt of the sea4 ,they are largely silicates--that is1 they contain silicon and oxygen4 7,silicon is a nonmetallic element1 always found in combination with something else4 ,it is second only to oxygen as the chief elementary constituent of the earth's crust47 ,other rock-forming minerals are the large family of micas1 with names like muscovite and phlogopite4 ,there are the feldspars1 including albite and orthoclase4 ,others are amphiboles1 pyroxenes1 zeolites1 garnets and many others you may never find or hear about unless you become a true mineralogist4 ,a rock may be made almost entirely of one mineral or of more than one mineral4 ,rocks containing different combinations of the same minerals are different4 ,even two things made of the same single mineral can be quite different4 ,carbon may turn up as a lump of coal or a diamond4 ,how ,minerals ,got ,their ,names ,names of most minerals end in ite--apatite1 calcite1 dolomite1 fluorite4 ,but many do not3 amphibole1 copper 7the most common pure metal in rocks71 feldspar1 galena1 gypsum1 hornblende1 mica1 quartz4 ,many minerals take their names from a ,greek word referring to some outstanding property of the mineral4 ,for example1 hematite1 an oxide of iron1 was named about #cbe ,b4,c4 from the ,greek ,,haima1 or blood1 because of the color of its powder4 ,some minerals are named for the locality in which they were first discovered4 ,coloradoite was first found in ,colorado4 ,benitoite turned up in ,san ,benito ,county1 ,california4 ,and so with labradorite and brazilite4 ,other minerals got their names from famous people4 ,willemite was named in honor of ,willem ,i1 ,king of the ,netherlands4 ,the great ,german poet-philosopher1 ,goethe1 could turn up in your collection as goethite4 ,and there's smithsonite1 named for ,james ,smithson1 founder of the ,smithsonian ,institution4 figure captions ,gold1 jasper1 uncut diamond1 quartz 7violet in color71 halite 7,carlsbad ,n4,m471 calcite 7,s4 ,dakota71 copper1 turquoise 7brilliant color7 ,out ,of ,this ,world ,some minerals come from outer space4 ,they're meteorites1 which are rock fragments4 ,every day1 hundreds of millions of them enter the earth's atmosphere4 ,most of them1 however1 are burned up by the heat from air friction and never reach the ground4 ,meteors large enough to reach the earth are called meteorites4 ,most minerals found in meteorites are the same as those we have on earth4 ,but1 there are some rare minerals known only in meteorites4 ,two of them are cohenite and schreibersite4 ,,main ,,kinds ,,of ,,rocks ,rocks are the building blocks of the earth's crust4 ,they may be massive1 as in granite ledges1 or tiny4 ,soil1 gravel1 sand and clay are rocks4 ,,there ,,are ,,three ,,main ,,types ,,of ,,rocks4 #a4 ,,igneous rocks are those formed at very high temperatures or from molten materials4 ,they come from magmas--molten mixtures of minerals1 often containing gases4 ,they come from deep below the surface of the earth4 ,if they cool off while below the surface1 they form intrusive rocks1 which may later be revealed by erosion4 ,when magmas reach the surface red hot1 they form extrusive rocks1 such as volcanic rocks4 ,thus1 granite is an igneous1 intrusive rock2 lava is an igneous1 extrusive rock4 7,notice how the type of rock tells its past history--if you know what to look for47 #b4 ,,sedimentary rocks are formed by the action of wind1 water1 or organisms4 ,they cover about three quarters of the ,earth's surface4 ,most are laid down--as sediments--on the bottom of rivers1 lakes and seas4 ,many have been moved by water1 wind1 waves1 currents1 ice or gravity4 ,the most common sedimentary rocks are sandstones1 limestones1 conglomerates and shales4 ,oil is found in sedimentary formations4 #c4 ,,metamorphic rocks are those that have been changed from what they were at first into something else--by heat1 pressure1 or chemical action4 ,all kinds of rocks can be changed4 ,the result is a new crystalline structure1 the formation of new minerals1 or a change in the rock's texture4 ,slate was once shale4 ,marble came from limestone4 ,gneiss 7pronounced nice7 is perhaps reworked granite4 figure captions ,igneous rocks are formed at high temperatures or from molten materials4 ,they come from deep beneath the earth4 ,they can be intrusive or extrusive--depending on where they cooled off4 ,sedimentary rocks are formed by the action of wind1 water1 or organisms4 ,they usually are laid down on the bottom of rivers1 lakes and seas4 ,most of the earth's surface is covered by these rocks4 ,oil is found in sedimentary formations4 ,metamorphic rocks have been changed from their original state into something else4 ,heat1 pressure1 chemical action change the crystalline structure1 the texture1 even form new minerals4 ,all kinds of rock can be changed4 ,a ,word ,on ,fossils ,perhaps you'll find rocks containing fossils--or even fossils by themselves4 ,they should form a separate part of your collection4 ,fossils are the remains--or the outlines--of former plant or animal life buried in rock4 ,the older the rock1 the simpler the plant and animal life it contains4 ,thus fossils can give a clue to the age of the rock strata4 ,fossils can teach history4 ,they tell us about plants and animals that are now extinct--the dinosaur1 for example4 ,they can also tell of ancient climates4 ,coral found in rocks in ,greenland suggests it must have once been warm4 ,remains of fir and spruce trees have been found in the tropics4 ,how are fossils formed8 ,teeth1 bone and wood don't last long in their original state4 ,however1 buried materials decompose1 leaving a film of carbon as a fossil4 ,this results in a leaf tracery1 or the outlines of some simple animal4 ,on a gigantic scale1 this process of forming carbon has resulted in our great coal deposits4 ,sometimes the buried material is gradually replaced by silica or other substances1 making petrified objects4 ,wood can be replaced--cell by cell--by agate or opal from silica-bearing water4 ,the result is petrified wood1 the finest examples of which can be found in our ,petrified ,forest ,national ,park in ,arizona4 ,this can happen to shells1 too4 ,how about molds and casts of footprints of ancient animals8 ,a brontosaurus might have stomped along in soft1 warm mud eons ago4 ,the mud hardened and later another layer of soft earth covered the print1 preserving it4 ,,collecting ,if you want to collect rocks and minerals just for the sake of having them1 you can buy specimens4 ,many can be purchased for #be cents to #a each1 while a rare specimen can cost hundreds of dollars4 ,the true pleasure is in finding your own samples4 ,later1 when you have a good-sized collection1 you can fill gaps by buying specimens or swapping extras with other collectors4 ,you'll be amazed at the number of amateur collectors4 ,perhaps no branch of science owes more to the work of amateurs than mineralogy4 ,our great collection of minerals in the ,u4,s4 ,national ,museum in ,washington1 ,d4,c41 was gathered almost entirely by two amateurs who devoted many years and much money to their hobby4 ,where ,to ,look ,look for pebbles by the roadside1 in beds of streams and riverbanks4 ,go out into the country for ledges on hillsides4 ,every road cut1 cliff1 bank1 excavation1 or quarry shows rocks and minerals4 ,railroad cuts1 rock pits1 dump piles around mines1 building sites--they'll all yield specimens4 ,some of the best mineral specimens collected in ,new ,york ,city came from skyscraper and subway excavations4 ,help a ,new ,england farmer clear his field and you'll have more rocks than you know what to do with4 ,as for reference books1 many states publish guides to mineral deposits4 ,mineralogical magazines list mineral localities4 ,tips ,for ,the ,field ,don't try to collect too much at once4 ,work early in the day or late in the afternoon4 ,a hot sun on bare rock can make you sizzle--especially if you're loaded with equipment and samples4 ,here's the equipment to take3 newspapers for wrapping samples1 notebook and pencil1 geologist's pick1 cold chisel1 magnifying glass1 compass1 heavy gloves1 a knife1 and a knapsack4 ,later on1 you may want a ,geiger counter for spotting radioactive rocks4 ,be selective4 ,hand-sized specimens are best4 ,if your sample is too large1 trim it to size1 showing its most striking feature to best advantage4 ,when you wrap the sample in newspaper1 include a note telling when and where you found it4 ,this information will be transcribed to a filing card when you add the specimens to your display1 so make it as complete and accurate as you can4 ,when you get home1 clean specimens with soapy1 warm water1 applied with a soft brush4 ,soluble minerals like halite can't be washed1 but should be rinsed with alcohol4 ,a coat of clear lacquer will protect some samples against dirt4 ,arranging ,your ,collection ,put a spot of enamel on the specimen4 ,write on the spot--in ,india ink--a catalog number and have this number refer to a card in a file drawer4 ,the card should list date1 place found1 identification of specimen1 etc4 ,group your samples3 metallic minerals1 semiprecious stones1 nonmetallic minerals4 ,display them on a shelf1 or buy or build a mineral cabinet with partitioned drawers4 ,for smaller samples1 use a ,riker mount with a glass top4 figure captions ,a common rock ,here's the equipment to take3 newspapers for wrapping samples1 notebook and pencil1 geologist's pick1 cold chisel1 magnifying glass1 compass1 heavy gloves1 a knife1 and a knapsack4 ,what ,do ,i ,have8 ,how do you identify specimens8 ,get books and magazines on rocks and minerals4 ,many have colored pictures that help4 ,but identification is best made by noting the physical characteristics of the rock or mineral4 ,for minerals1 there's a hardness scale in which a mineral of the higher number can scratch a mineral of the lower number but not be scratched by it4 ,the scale is3 #a7 talc2 #b7;gypsum2 #c7 calcite2 #d7 fluorite2 #e7 apatite2 #f7 orthoclase2 #g7 quartz2 #h7 topaz2 #i7 corundum2 #aj7 diamond4 ,remember it by this silly sentence3 ,the girls can flirt and other queer things can do4 ,when on a trip1 remember that a fingernail has a hardness of #b4e2 a penny1 #c2 a knife blade1 #e4e2 and a steel file1 #f4e4 ,use these to scratch your sample and you can get an approximate idea of its hardness4 ,you can buy a set of hardness points4 ,they're pointed pieces of minerals set in brass tubes1 each marked with its hardness scale4 ,the set costs about #cj 7half that if you assemble your own74 ,other tests for identifying minerals include specific gravity 7weight of mineral compared to the weight of an equal volume of water71 optical properties and crystal form1 color and luster4 ,minerals differ in cleavage and fracture 7how they come apart when cut74 ,they leave distinctive streaks on unglazed porcelain4 ,some are magnetic1 some have electrical properties1 some glow under ultraviolet or black light1 some are radioactive1 some fuse under a low flame while others are unaffected4 ,many studies with the dissolved mineral can identify it beyond doubt4 ,but most of these are too complicated for the beginner4 ,as you read1 look at pictures and samples1 and talk with other rockhounds or leaders of mineralogy clubs1 you'll get better at identifying rocks4 ,museum experts and your state's geologist can help1 too4 figure captions ,specific gravity balance ,blowpipe analysis ,,gems ,,for ,,the ,,lucky ,,few ,if you're lucky1 you'll find gems or semiprecious stones4 ,gems are the finer1 more crystalline forms of minerals which are ordinarily less beautiful and spectacular4 ,the true gems are diamonds1 emeralds1 rubies and sapphires4 ,all others are semiprecious and ornamental4 ,diamonds are pure carbon1 but did you know that rubies and sapphires are corundum minerals--rare forms of alumina4 ,in slightly different form1 they'd turn up on emery paper4 ,other stones you might find are the quartz gems3 rose quartz1 amethyst1 rock crystal1 agate1 jasper1 bloodstone4 ,or opaque gems such as jade1 moonstone1 lapis-lazuli1 obsidian1 and turquoise4 ,you don't have to find them4 ,you can buy gems in the rough or in blanks1 then cut and polish them to make your own jewelry or decorations4 ,this takes practice1 plus a cutting and polishing outfit1 wood vise1 maybe a diamond wheel4 7,or you can join a lapidary club that might already have the equipment74 ,first learn to make cabochons--stones with round or curved surfaces4 ,then try cutting facets 7or faces7 in transparent gems4 ,learn by reading1 working with an expert1 trial and error4 ,making jewelry is fun1 and collecting gems is as interesting as collecting rocks and minerals2 it brings the world into your home4 ,from the ,west come agates1 jaspers1 petrified woods2 from the ,east1 colorful marbles1 serpentines1 granites4 ,alaska1 ,idaho1 ,connecticut or ,austria will yield dark red garnets4 ,fine moonstones come from ,ontario2 quartz crystals from ,hot ,springs1 ,arkansas1 can be compared with similar ones from the ,swiss ,alps or ,brazil4 ,rock collecting is a hobby you can tailor to your taste4 ,but whether you concentrate on an area close to home or travel across whole continents1 you'll find that the pleasure and knowledge you gain from your collection are matched by the fun and adventure of the search4 figure captions ,drop sticks to hold stones ,diamond cutting wheel ,,back ,,cover ,a ,brontosaurus ,shell ,oil ,company ,revised #h_/hh