- 1982 : Création de la société Autodesk et annonce et commercialisation de la 1re version d’AutoCAD
- 1985 : Autodesk entre en bourse et devient la 1re société de CAO sur PC à ouvrir son capital au public
- 1990 : Autodesk crée la division Multimédia, et annonce 3D Studio
- 1995 : Autodesk se réorganise en groupes marché
- 1996 : Autodesk crée la division Kinetix pour ses produits multimédia
- 1998 : Autodesk acquiert certains actifs CAO/DAO Mécanique de Genius-CAD Software et dépasse les 2 millions de licences AutoCAD vendues dans le monde
- 1999 : Autodesk dépasse la barre des 4 000 000 d’utilisateurs dans le monde, acquiert Discreet Logic et Kinetix, créateur de 3D Studio Max qui sont fusionnés dans la division Discreet, fait l’acquisition de Vision* Solutions basée à Ottawa, Canada, livre sa millionième licence de AutoCAD LT et prend le virage Internet
- 2000 : Autodesk annonce qu'elle met l’accent sur la formation en ligne et lance sa gamme intégrée à Internet iDesign 2001.
- 2003 : Autodesk lance AutoCAD 2004, la nouvelle version de la plate-forme AutoCAD et Inventor 8. Autodesk fait l’acquisition de trois éditeurs de logiciels : truEInnovations Inc., VIA Development Corporation et Linius Technologies Inc.
- 2004 : Autodesk lance AutoCAD 2005.
- 2005 : Autodesk lance AutoCAD 2006. Les résultats financiers d'Autodesk Inc. dépassent la barre du milliard de dollars pour la première fois, avec un chiffre d'affaires de 1,234 milliard de dollars. Autodesk fait l'acquisition de trois éditeurs de logiciel : Compass, c-plan et surtout Alias Systems Corporation (éditeurs du logiciel Maya, concurrent direct de 3D Studio Max, montant du rachat : 182 millions de $). La division Discreet est rebaptisée MED (Media and Entertainment Division).
- 2006 :
- Autodesk lance AutoCAD 2007 et la première version de Civil 3D (2006).
- Carl Bass est nommé Président et CEO.
- Autodesk acquiert Constructware
- 2007 : Autodesk acquiert NavisWorks, Opticore, Skymatter (Mudbox), PlassoTech et Robobat.
- 2008 : Autodesk dépasse pour la première fois de son histoire le seuil des 2 milliards de dollars de chiffre d'affaires avec 2,172 milliards de $. Autodesk achète Softimage pour 35 millions $ US1. L'entreprise acquiert également Realviz, Kynogon, Moldflow, ALGOR, et les technologies ECSCAD et iLogic.
- 2009 : Autodesk licencie 10 % de ses effectifs suite à la crise économique
- 2013 : Autodesk rachète Delcam pour 277 millions de dollars2.
jeudi 12 décembre 2013
Telecharger robobat gratuitement
vendredi 29 novembre 2013
How to Make a Rainbow Loom Fishtail Bracelet
It's easy to see why Rainbow Loom bracelets are super-popular with school-age kids. They are colorful, fun to make, and look absolutely awesome when worn together in a bunch or one at a time. And because they're made of stretchy rubber, then can be easily removed and put back on, and kids don't have to worry about getting them wet. It's the perfect combination of craft and jewelry for kids.
These fishtail bracelets can be made with or without a full-size Rainbow Loom. Here are some easy step-by-step instructions for how to make a rubberband fishtail bracelet using a mini Rainbow Loom. If you are using a full-size loom, you can simply use any two pegs instead of the mini loom.
Kids can make this Rainbow Loom fishtail bracelet with alternating colors or group colors together to form a rainbow or other design pattern. Encourage them to use their imagination to make their own designs!
Rainbow Loom bracelets a hot kid trend
My daughter came home from a friend's house one day recently with a bracelet made from small, interlocking, colorful rubber bands. Soon she had another made by another friend. Then another made by a classmate. Then we heard the bracelets mentioned at Girl Scouts. And then my 8-year-old was invited to a class to learn to make the bracelets on her own. Eventually, it dawned on me that these Rainbow Loom bracelets were the new big thing.
And they are, at least among elementary school kids, it seems. I was clueless until a month or so ago, but Rainbow Loom has been enthralling kids for a while now, so says the New York Times.
If you are like I was and not in the know, a Rainbow Loom is a plastic, peg-board-like device on which you weave, or pull, tiny rubber bands into cool bracelets. (You can also work the bands into bracelets without the loom.)
A sure sign of its popularity: The bracelets and devices have been banned from one New York City school, apparently for being too distracting and prompting playground fights.
Also: My daughter and her friend -- a fellow kid with a Rainbow Loom -- both showed up at their softball game Saturday with brightly colored bracelets on their wrists. Two teammates saw them and squealed, "Rainbow Loom!"
So yeah, it's big. And yeah, it's weird how these things seem to just take over. But at least unlike Beanie Babies or Silly Bandz, this fad isn't just about buying. The making is the thing. My daughter had a sleepover, and she and her buddy spent most of the time "looming" the host mom said. They also did research, watching videos on how to do different patterns and quickly mastering more intricate designs.
When my daughter returned home the next day, she went right to her room with her loom and made more bracelets, fancier ones than I'd seen before. She did that until she ran out of her stash of rubber bands.
So now it is about buying because she needs more rubber bands, please. But it is mostly about the crafting -- and also about giving. She has bracelets made by friends, and she made me a bracelet, and she made one for her brother, in his hockey team colors. He even wore it to school, declaring it "cool."
So as fads go, I can deal with Rainbow Loom, though the supplies aren't offered everywhere. I'll be in search of more tiny rubber bands as soon as I have a few free minutes. ...
dimanche 27 octobre 2013
How to Create Pop Art Nails
Step 1 of 7
First start off with cleaning your nails, then place a base coat on your nails to protect them from staining
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samedi 28 septembre 2013
VISA: A card to suit every lifestyle
Whoever you are and whatever your lifestyle, there is a Visa card to suit you.
Millions of people already rely on Visa cards because they are safer and more convenient than carrying cash and can be used to buy goods and services all over the world by mail and telephone order and on the Internet, as well as in ordinary stores.
Visa is welcomed at shops, hotels, restaurants, petrol stations and other locations worldwide. If you need cash, there are more than a million cash dispensers, where you can withdraw local currency at any time of the day or night.
And, unlike cash, a Visa card can be quickly cancelled and replaced if it is lost, however far you are from home.
With a Visa card you can pay now, pay in advance or pay later whichever option best matches your needs. Click on the links to find out more.
Millions of people already rely on Visa cards because they are safer and more convenient than carrying cash and can be used to buy goods and services all over the world by mail and telephone order and on the Internet, as well as in ordinary stores.Visa is welcomed at shops, hotels, restaurants, petrol stations and other locations worldwide. If you need cash, there are more than a million cash dispensers, where you can withdraw local currency at any time of the day or night.
And, unlike cash, a Visa card can be quickly cancelled and replaced if it is lost, however far you are from home.
With a Visa card you can pay now, pay in advance or pay later whichever option best matches your needs. Click on the links to find out more.
credit report and credit score
| Check your credit report and credit score with toll-free support, business credit reports , identity theft protection, and marketing solutions - Experian Official Site. Experian 's SmartBusinessReports offer small- business professionals like you an easy and economical way to obtain instant business credit reports online. Business Credit Reports is the only tri-merge business credit report provider that includes company credit information from Experian , Equifax, & D&B with an overall. Check Someone Else's Credit For $0 Your Customers And Clients Buy Their Credit Report And Securely Grant You Access Through Experian ®. Learn More Your source for Experian Business Credit Reports and Scores. Important glossary terms used on this site: Company credit reports , Company credit report , Business. Check your credit report and score from Experian UK. Our free credit check provides your credit history and rating online Free guides for the credit professional Experian have developed a range of free guides to help credit professionals. The series of free guides will. | |
| Check your credit report and credit score with toll-free support, business credit reports , identity theft protection, and marketing solutions - Experian Official Site. Experian small business services offering mailing lists, email marketing, business credit reports , customer credit checks, and collection products to help you succeed. Experian 's SmartBusinessReports offer small- business professionals like you an easy and economical way to obtain instant business credit reports online. Get your free Experian credit report . CreditExpert from Experian can help you improve your credit score, protect your identity and take control of your finances. Your source for Experian Business Credit Reports and Scores. Important glossary terms used on this site: Company credit reports , Company credit report , Business. Check your credit report and score from Experian UK. Our free credit check provides your credit history and rating online Check your consumer credit score, free credit report , credit history, business credit reports and marketing solutions from Experian .co.za | |
lundi 23 septembre 2013
Grand Theft Auto Online could support microtransactions through 'Cash Cards'
Grand Theft Auto Online, the multiplayer component which will be free for all Grand Theft Auto 5 players, could support microtransactions. According to Redditor 1880, the store section of GTA 5 (which currently has nothing available yet) points to a file that allegedly references something called "Cash Cards."
The XML file (also copied toPastebin), specifically mentions four separate Cash Cards that range in value from $100,000 to $1,250,000.
"Cash is king in this town. Solve your money problems and help get what you want across Los Santos and Blaine County with the purchase of cash packs for Grand Theft Auto Online," the description for each of the four Cash Cards reads. "All purchased cash is automatically deposited into your character’s bank account. Spend wisely, cash therapy is fleeting."
Rockstar has yet to formally announce any plans for microtransactions, but this certainly seems like it could be implemented following the launch of Grand Theft Auto Online. The multiplayer mode is expected to release on October 1st and will be free for anyone who has already purchased Grand Theft Auto 5.
How do you feel about the possibility of being able to purchase in-game money with real-life money?
GTA 5 Cheats: Saving money with the Ammu-Nation discount
Things can get pretty expensive in Grand Theft Auto 5. While we've offered a few ways to earn a quick buck, another way is to simply save through discounts. Ammo can get pretty expensive, so one of the things you'll want to do is unlock the store discounts.
By completing all of the Gun Range challenges you'll receive a 15% discount at all Ammu-Nation stores. Getting gold rankings for all of the challenges will increase the discount to 25% total.
Check out our full list of GTA 5 cheats for Xbox 360 and PlayStation 3.
how to get to Brooklyn Navy Yard
The Brooklyn Navy Yard is located on Brooklyn’s waterfront between the Williamsburg and Manhattan Bridges and surrounded by DUMBO/Vinegar Hill, Fort Greene and Williamsburg sections of Brooklyn.
Looking for information on the Brooklyn Navy Yard Center at BLDG 92? Explore our exhbition and visitors center online and find out what we've been up to.
View a map of the Yard for entry gates.
Bike
The Yard is bike-friendly with bike lanes and bike racks throughout. Additionally, the City's bike share program has stations located both inside and surrounding the Yard. For a map of bike share stations, please click here.
Shuttle
Shuttle service is available at any of the entry gates to the building you're visiting and from local subway stations. Click here for the full Shuttle Schedule.
Bus
Bus Lines - B48, B57, B62, B69
Take the B57 or the B69 to Cumberland Street and Flushing Avenue.
Take the B62 to Vanderbilt and Park Avenues and walk one block to Flushing Avenue.
Take the B48 to Flushing and Classon Avenues. Walk under the overpass on Flushing Ave. Continue down Flushing Avenue until you reach the Clinton Avenue security gate.
Take the B48 to Flushing and Franklin Avenues. Transfer to the B57 heading towards Downtown/Fulton Street; get off at Flushing and Vanderbilt Avenues.
Subway
The Brooklyn Navy Yard's Sands Street gate is a 15 minute walk from the A/C train at High Street or F train at York Street.
Take A or C train to High Street/Brooklyn Bridge:
Exit on Adams Street.
Option 1: Take the B69 bus runs along Flushing Avenue. YGet off at Cumberland Street or Clinton Avenue to access entry gates.
Option 2: Make a right upon exiting subway station. Walk down Sands Street until you reach the security gate.
Take the F train to York Street:
Option 1: Transfer to the B62 at York and Gold Streets going toward Long Island City. Get off at Cumberland Street OR Clinton Avenue. Walk one block to Flushing Avenue.
Option 2: Exit the train and make a right on York Street. Follow York until it intersects Navy Street. Make a right on Navy Street and enter through Sands Street security gate.
Take the G train to Clinton/Washington Avenue:
Walk down Lafayette Avenue. Make a left on Clinton Avenue. Continue on Clinton until you get to Flushing Avenue security gate.
By Car
Address for mapping online or using a GPS navigator: 63 Flushing Avenue, Brooklyn, NY 11205
Cafe/Space Rental Information
Ted & Honey Cafe is located at BLDG 92 and is accessible to the public from Flushing and Carlton Avenues. Ted & Honey was founded upon the principles of sustainability, use of local products, and high quality at an affordable price.
how to Download a YouTube video
Download a YouTube video from any web page.
Save a YouTube video as an MP3 file, iPod file, FLV file, MP4 file, AVI file, and more!
Support for DailyMotion, Facebook, Break, MetaCafe, FunnyOrDie, Vimeo, and some adult sites. More sites added soon.
FASTER: Just type
pwn to download YouTube videos!
HTTPS → HTTP
Instructions
- View a video on YouTube.
- In the URL location box, type
pwnin front ofyoutube, and enter. - Get links to download the video. ( no software, no copy/paste! )
Instructional Videos
Cupcakes maken met het basisrecept cupcakes
Wil je graag zelf de lekkerste en mooiste cupcakes maken? Met het basisrecept van Cupcakerecepten.nl maak je in een handomdraai de heerlijkste en mooiste cupcakes zelf. Volg het recept stap voor stap, dan gaat het je zeker lukken!
Informatie
- Voorbereidingstijd:
- Baktijd:
- Recept voor 12 cupcakes
- Portie: 1 cupcake
- Calorieën per portie: 170
Ingrediënten
- 125 Gram roomboter op kamertemperatuur
- 125 Gram kristalsuiker
- 125 Gram zelfrijzend bakmeel
- 2 Eetlepels melk op kamertemperatuur
- 2 Eieren op kamertemperatuur
Bereidingswijze
Voorbereiding
Verwarm de oven voor op 170 graden en zorg ervoor dat het rooster in het midden van de oven geplaatst is. Hier kun je later makkelijk je cupcake bakblik op plaatsen.
Zet een cupcake bakblik met daarin papieren bakvormpjes klaar. Als je een cupcake bakblik gebruikt blijven de cupcakes beter in vorm tijdens het bakproces en het is zo ook makkelijker om de vormpjes te vullen met beslag.
Haal de boter, eieren en melk tijdig uit de koelkast om ze op kamertemperatuur te laten komen. Snij de boter in kleine blokjes. Meet alle ingrediënten van te voren af met een maatbeker of weegschaal en zet ze in aparte kommen klaar voor gebruik. Doe het meetwerk secuur, dit is cruciaal voor een goed cupcake beslag.
Zet ook het volgende klaar: 1 grote kom, 1 mixer met beslag haken, 2 eetlepels, 1 houten prikker, 1 (afkoel)rooster.
Beslag maken
Het is belangrijk dat de boter goed op kamertemperatuur is gekomen. Dit betekent dat je de boter tijdig uit de koelkast haalt, zodat de boter zacht is voor gebruik (niet smelten). Doe de boter in een kom en voeg de suiker beetje bij beetje toe. Mix het mengsel steeds tussendoor met de mixer op middelhoge snelheid. Hierdoor kan de suiker beter worden opgenomen door de boter en wordt je beslag luchtiger. Mix de boter en de suiker goed door elkaar, totdat er een lichte en luchtige massa ontstaat.
Voeg nu 1 voor 1 de eieren toe. Let op: ook de eieren haal je op tijd uit de koeling en laat je op kamertemperatuur komen. Hierdoor wordt je beslag luchtiger. Mix het beslag goed door met de mixer op middelhoge snelheid als je een ei hebt toegevoegd.
Voeg nu beetje bij beetje het zelfrijzend bakmeel toe. Mix telkens de massa met de mixer op middelhoge snelheid als je een hoeveelheid meel hebt toegevoegd.
Als laatste voeg je de melk toe en mix je nog eens 1 minuut alles goed door elkaar met de mixer op middelhoge snelheid, tot een luchtig en glad beslag. Pak je cupcake bakblik erbij met daarin de papieren bakvormpjes. Het vullen gaat nu heel makkelijk. Neem een eetlepel en schep een beetje beslag in het midden van het papieren cupcake vormpje. Met een tweede lepel of spatel schraap je het beslag van de lepel in het vormpje.
Vul de papieren bakvormpjes tot 2/3 vol. Zo kunnen de cakejes goed rijzen en zullen ze niet boven het papieren vormpje uit steken als ze klaar zijn. Hoe platter de cupcakes zijn als ze gebakken zijn, hoe makkelijker je ze kan decoreren!
Bakken
Open de oven en zet het cupcake bakblik in het midden van de oven op het rooster. Mocht je een magnetron gebruiken met ovenfunctie waarvan de plaat rond draait is dit geen enkel probleem. Bak de cupcakes 20-25 minuten in de oven op 170 graden. Open de ovendeur tussentijds niet, anders zakken de cupcakes misschien in. Na 20 minuten open je de ovendeur en prik je met een houten prikker in een cupcake om te controleren of de cupcakes gaar zijn. Wanneer er geen nat beslag aan de houten prikker blijft kleven kunnen de cupcakes uit de oven gehaald worden. Kleeft er nog wel nat beslag aan de houten prikker, dan laat je de cupcakes nog 5 minuten in de oven bakken. Controleer na 5 minuten weer of de cupcakes gaar zijn en haal ze uit de oven als dat zo is. Let op: iedere oven is anders, hierdoor kan de baktijd van je cupcakes verschillen met de door ons aangegeven baktijden.
Afkoelen
Eenmaal uit de oven laat je de cupcakes even een minuut in het bakblik zitten. Zet het bakblik bij voorkeur even op een rooster. Na een minuut haal je de cupcakes voorzichtig uit het bakblik. Je kunt het bakblik een beetje schuin houden zodat de cupcakes er langzaam uitvallen. Zo hoef je niet aan de papieren bakvormpjes te trekken en laten de papiertjes niet los. De papieren bakvormpjes laat je om de cupcakes zitten. Laat de cupcakes goed afkoelen op een koel rooster.
Zijn je cupcakes iets boller geworden dan gewenst, leg dan meteen nadat je de cupcakes uit de oven hebt gehaald een snijplankje op de cupcakes in het cupcake bakblik. Na ongeveer 1/2 minuut haal je het plankje er weer van af, je cupcakes zijn nu mooi plat.
Eenmaal afgekoeld zijn de cupcakes klaar om verder te decoreren met een topping, eetbare decoraties en andere leuke cupcakeproducten! Decoreer de cupcakes met behulp van de basis decoratiematerialen, verkrijgbaar in de webshop.
- Kijk hier voor hetbasisrecept frosting.
- Verse cupcakes die op de dag zelf zijn gemaakt zijn het allerlekkerst.
- Bewaar de gebakken en afgekoelde cupcakes 1 tot 3 dagen in een luchtdichte doos, buiten de koelkast.De cupcakes blijven zo lekker luchtig en smeuig van binnen. Gebruik bij voorkeur een goed afsluitbare kunststof doos, type Tupperware.
- Kijk hier voor meer tips!
United States Diamond Mines and Mining: how and where to find Diamond in the United States
One Active Mine Today ...The United States only has two locations that have been operated as commercial diamond mines. One was the Kelsey Lake Diamond Mine near Fort Collins, Colorado. It produced small amounts of diamonds between 1996 and 2002 when the mine was closed due to legal problems. The second is at Crater of Diamonds State Park near Murfreesboro, Arkansas. It was worked as a commercial diamond mine in the early 1900s but closed because the deposit was subeconomic. It has since been operated by the State of Arkansas as a tourist "pay-to-dig mine" where anyone can pay a fee, look for diamonds and keep any that they find. A few hundred carats of diamonds are found there each year. Diamonds, diamond indicator mineral assemblages and potentially diamondiferous rocks have been found at hundreds of locations within the United States. One or more of these locations could become commercial and make the United States a significant producer of gem-quality diamonds. [1] Crater of Diamonds - The Only Active U. S. MineAlthough millions of carats of diamonds are consumed each year in the United States, only a few hundred carats are domestically produced. The only active diamond mine in the country is the Crater of Diamonds Mine near Murfreesboro, Pike County, Arkansas. There, recreational prospectors have been finding a few hundred carats of diamonds per year since the early 1970s. Most of the stones are white, yellow and brown in color but a wide range of diamond colors has been found at the mine. See photo at top right.  >> The only diamond mine where you can be the miner. <<The mine is a dig-for-fee operation maintained by the Crater of Diamonds State Park. The diamonds are hosted in a lamproite breccia tuff and its overlying soil in a structure known as a maar. Collectors pay a fee of a few dollars per day to prospect and can keep any diamonds that they find. This is the only diamond mine in the world that is open to the public. Crater of Diamonds has produced several significant finds. These include: The "Strawn-Wagner Diamond" This diamond was found at the Park as a 3.03 carat rough stone in 1990 by Shirley Strawn. In 1997 it was cut to yield a 1.09 carat, "round brilliant" stone that received a perfect grading of 0/0/0 from the American Gem Society. It stands as the most perfect diamond the American Gem Society has ever certified. [2] The "Uncle Sam" Diamond The "Uncle Sam" is a 40.23 carat white diamond that stands as the largest diamond ever found in North America. It was found at the Crater of Diamonds in 1924 before the property was opened as a State park. [2] The Kahn Canary Diamond This 4.25-carat, canary-color diamond with a perfect dodecahedral pillow shape was found in 1977 by George Stepp. Stan Kahn purchased the diamond from Stepp and did not have it cut because even in its rough shape it is an especially beautiful gem. Kahn has shared the stone with the public by loaning it to museums around the world for temporary display. Kelsey Lake MineAt present, there are no commercial diamond mines operating in the United States. The only commercial mine with recent activity is the Kelsey Lake Diamond Mine, located near Fort Collins, Colorado on the state boundary between Colorado and Wyoming. Kelsey Lake was opened as a commercial diamond mine by Redaurum Limited in 1996. Great Western Diamond Company, a wholly-owned subsidiary of McKenzie Bay International Limited, purchased the property in 2000 and operated the mine until 2002. It was closed due to legal problems rather than a lack of diamonds. [4] Most of the diamonds produced at the Kelsey Lake Mine were clear, gem-quality stones. About one-third of the stones were one carat or larger in size. When the mine closed there was an identified resource of 17 million tons of ore with an average grade of 4 carats per hundred metric tons. In 2003 the United States Geological Survey reported that the most valuable stones produced from the Kelsey Lake Mine were valued at $89,000 and $300,000. [3] Wyoming Diamond DepositsThe Wyoming Geological Survey believes that a billion-dollar diamond industry could develop in their state. Wyoming has comparable conditions to the Canadian deposits and hundreds of kimberlite pipes are believed to exist. Their website has maps showing the location of diamond-hosting intrusives, reported placer diamonds, kimberlite indicator mineral anomalies, lamproites and diamond stability indicator minerals. [4] Some points that communicate their optimism for a significant diamond industry in Wyoming [5]:
Other Potential Diamond AreasThe discovery of numerous commercial diamond deposits in Canada has generated prospecting interest in the United States. Areas with similar geologic settings to the Canadian deposits exist in Alaska, Colorado, Minnesota, Montana, and Wyoming. Diamond indicators and confirmed diamond pipes have been found but so far none have attracted significant investments or commercial mining. Hundreds of diamonds have been found in the Pacific coast region; however, that area is unfavorable for the presence of kimberlite and lamproite. It is possible that these diamonds are coming from a source that has yet to be understood. [5] Finally, several companies in the United States are now producingsynthetic diamond using chemical vapor deposition and other processes. The diamond produced by these companies can be used as gemstones or as high-performance materials in manufacturing processes. Synthetic diamonds have a large number of uses and have replaced natural diamonds in most industrial processes. Contributor: Hobart King
More from Geology.com
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Gold Prospecting in the United States: how to find gold in the United States
The Many Rewards of Finding GoldAnyone who pans for gold hopes to be rewarded by the glitter of colors in the fine material collected in the bottom of the pan. Although the exercise and outdoor activity experienced in prospecting are rewarding, there are few thrills comparable to finding gold. Even an assay report showing an appreciable content of gold in a sample obtained from a lode deposit is exciting. The would-be prospector hoping for financial gain, however, should carefully consider all the pertinent facts before deciding on a prospecting venture. Few Prospectors Find Valuable Gold DepositsOnly a few prospectors among the many thousands who searched the western part of the United States ever found a valuable deposit. Most of the gold mining districts in the West were located by pioneers, many of whom were experienced gold miners from the southern Appalachian region, but even in colonial times only a small proportion of the gold seekers were successful. The US Has Been Heavily ProspectedOver the past several centuries the country has been thoroughly searched by prospectors. During the depression of the 1930's, prospectors searched the better known gold-producing areas throughout the Nation, especially in the West, and the little-known areas as well. The results of their activities have never been fully documented, but incomplete records indicate that an extremely small percentage of the total number of active prospectors supported themselves by gold mining. Of the few significant discoveries reported, nearly all were made by prospectors of long experience who were familiar with the regions in which they were working. Prospect Where Gold Has Been Found Before
The development of new, highly sensitive, and relatively inexpensive methods of detecting gold, however, has greatly increased the possibility of discovering gold deposits which are too low grade to have been recognized earlier by the prospector using only a gold pan. These may be large enough to be exploited by modern mining and metallurgical techniques. The Carlin mine near Carlin, Nevada, produced gold from a large low-grade deposit that was opened in 1965 after intensive scientific and technical work had been completed. Similar investigations have led to the discovery of a Carlin-type gold deposit in Jerritt Canyon, Nevada. Many Placer Deposits Have Been Worked - TwiceMany believe that it is possible to make wages or better by panning gold in the streams of the West, particularly in regions where placer mining formerly flourished. However, most placer deposits have been thoroughly reworked at least twice--first by Chinese laborers, who arrived soon after the initial boom periods and recovered gold from the lower grade deposits and tailings left by the first miners, and later by itinerant miners during the 1930's. Geologists and engineers who systematically investigate remote parts of the country find small placer diggings and old prospect pits whose number and wide distribution imply few, if any, recognizable surface indications of metal-bearing deposits were overlooked by the earlier miners and prospectors. Financial Challenges of Gold ProspectingOne who contemplates prospecting for gold should realize that a successful venture does not necessarily mean large profits even if the discovery is developed into a producing mine. Although the price of gold has increased significantly since 1967 when the fixed price of $35 an ounce was terminated, the increases in the cost of virtually every supply and service item needed in prospecting and mining ventures have kept profit margins at moderate levels, particularly for the small mine operator. In general, wide fluctuations in the price of gold are not uncommon, whereas inflationary pressures are more persistent. The producer of gold, therefore, faces uncertain economic problems and should be aware of their effects on his operation. Knowledge of Laws and Property OwnershipToday's prospector must determine where prospecting is permitted and be aware of the regulations under which he is allowed to search for gold and other metals. Permission to enter upon privately owned land must be obtained from the land owner. Determination of land ownership and location and contact with the owner can be a time-consuming chore but one which has to be done before prospecting can begin. Determination of the location and extent of public lands open to mineral entry for prospecting and mining purposes also is a time consuming but necessary requirement. National parks, for example, are closed to prospecting. Certain lands under the jurisdiction of the Forest Service and the Bureau of Land Management may be entered for prospecting, but sets of rules and regulations govern entry. The following statement from a pamphlet issued in 1978 by the U.S. Department of the Interior and entitled "Staking a mining claim on Federal Lands" responds to the question "Where May I Prospect? "There are still areas where you may prospect, and if a discovery of a valuable, locatable mineral is made, you may stake a claim. These areas are mainly in Alaska, Arizona, Arkansas, California, Colorado, Florida, Idaho, Louisiana, Mississippi, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oregon, South Dakota, Utah, Washington, and Wyoming. Such areas are mainly unreserved, unappropriated Federal public lands administered by the Bureau of Land Management (BLM) of the U.S. Department of the Interior and in national forests administered by the Forest Service of the U.S. Department of Agriculture. Public land records in the proper BLM State Office will show you which lands are closed to mineral entry under the mining laws. These offices keep up-to-date land status plats that are available to the public for inspection. BLM is publishing a series of surface and mineral ownership maps that depict the general ownership pattern of public lands. These maps may be purchased at most BLM Offices. For a specific tract of land, it is advisable to check the official land records at the proper BLM State Office." Small Prospectors and Total Gold ProductionSuccessful gold mining under present conditions is a large-scale operation, utilizing costly and sophisticated machinery capable of handling many tons of low-grade ore each day. The grizzled prospector with a burro is no longer a significant participant in the search for mineral deposits, and the small producer accounts for only a minor share of the total production of metals including gold. Study, Persistence and Financial BackingSome degree of success in finding gold still remains for those choosing favorable areas after a careful study of mining records and the geology of the mining districts. Serious prospecting should not be attempted by anyone without sufficient capital to support a long and possibly discouraging campaign of preliminary work. The prospective gold seeker must have ample funds to travel to and from the region he selects to prospect and to support the venture. He must be prepared to undergo physical hardships, possess a car capable of traveling the roughest and steepest roads, and not be discouraged by repeated disappointments. Even if a discovery of value is not found, the venture will have been interesting and challenging. Public Information for Gold ProspectorsLocations of important gold-producing districts of the United States are shown in some of the reports of the United States Geological Survey listed at the bottom of this page. Geological surveys of the principal gold-producing States where additional information may be obtained also are listed. Information may be obtained, too, from U.S. Bureau of Mines State Liaison offices located in the capital cities of most States. There are also a large number of layman's books about gold that describe gold deposits and gold prospecting. The Geology of Placer DepositsA placer deposit is a concentration of a natural material that has accumulated in unconsolidated sediments of a stream bed, beach, or residual deposit. Gold derived by weathering or other process from lode deposits is likely to accumulate in placer deposits because of its weight and resistance to corrosion. In addition, its characteristically sun-yellow color makes it easily and quickly recognizable even in very small quantities. The gold pan or miner's pan is a shallow sheet-iron vessel with sloping sides and flat bottom used to wash gold-bearing gravel or other material containing heavy minerals. The process of washing material in a pan, referred to as "panning," is the simplest and most commonly used and least expensive method for a prospector to separate gold from the silt, sand, and gravel of the stream deposits. It is a tedious, back-breaking job and only with practice does one become proficient in the operation. California Placer DepositsMany placer districts in California have been mined on a large scale as recently as the mid-1950's. Streams draining the rich Mother Loderegion--the Feather, Mokelumne, American, Cosumnes, Calaveras, and Yuba Rivers--and the Trinity River in northern California have concentrated considerable quantities of gold in gravels. In addition, placers associated with gravels that are stream remnants from an older erosion cycle occur in the same general area. Alaska Placer DepositsMuch of the gold produced in Alaska was mined from placers. These deposits are widespread, occurring along many of the major rivers and their tributaries. Some ocean beach sands also have been productive. The principal placer-mining region has been the Yukon River basin which crosses central Alaska. Dredging operations in the Fairbanks district have been the most productive in the State. Beach deposits in the Nome district in the south-central part of the Seward Peninsula rank second among productive placer deposits of Alaska. Other highly productive placers have been found in the drainage basin of the Copper River and of the Kuskokwim River. Montana Placer DepositsIn Montana, the principal placer-mining districts are in the southwestern part of the State. The most productive placer deposit in the State was at Alder Gulch near Virginia City in Madison County. Other important placer localities are on the Missouri River in the Helena mining district. The famous Last Chance Gulch is the site of the city of Helena. There are many districts farther south on the headwaters and tributaries of the Missouri River, especially in Madison County which ranks third in total gold production in the State. Gold has been produced at many places on the headwaters of the Clark Fork of the Columbia River, particularly in the vicinity of Butte. Placer production from the Butte district, however, has been over-shadowed by the total output of byproduct gold recovered from the mining of lode deposits of copper, lead, and zinc. Idaho Placer Deposits
Oregon Placer DepositsThe most important mining regions of Oregon are in the northeastern part of the State where both lode and placer gold have been found. Placer gold occurs in many streams that drain the Blue and Wallowa Mountains. One of the most productive placer districts in this area is in the vicinity of Sumpter, on the upper Powder River. The Burnt River and its tributaries have yielded gold. Farther to the west, placer mining (particularly dredging) has been carried on for many years in the John Day River valley. In southwestern Oregon, tributaries of the Rogue River and neighboring streams in the Klamath Mountains have been sources of placer gold. Among the main producing districts in this region are the Greenback district in Josephine County and the Applegate district in Jackson County. South Dakota and WashingtonMinor amounts of placer gold have been produced in South Dakota (the Black Hills region, particularly in the Deadwood area, and on French Creek, near Custer) and in Washington (on the Columbia and Snake Rivers and their tributaries). Nevada, Arizona, New MexicoIn addition to these localities, placer gold occurs along many of the intermittent and ephemeral streams of arid regions in Nevada,Arizona, New Mexico, and southern California. In many of these places a large reserve of low-grade placer gold may exist, but the lack of a permanent water supply for conventional placer mining operations requires the use of expensive dry or semidry concentrating methods to recover the gold. Eastern US Placer DepositsIn the eastern States, limited amounts of gold have been washed from some streams draining the eastern slope of the southern Appalachian region in Maryland, Virginia, North Carolina, South Carolina, Georgia, and Alabama. Many saprolite (disintegrated somewhat decomposed rock that lies in its original place) deposits in this general region also have been mined by placer methods. Small quantities of gold have been mined by placer methods in some New England States. Additional placer deposits may be discovered in the East, but prospecting will require substantial expenditures of time and money. The deposits probably will be low grade, difficult to recognize, and costly to explore and sample. Moreover, most of the land in the East is privately owned, and prospecting can be done only with the prior permission and agreement of the land owner. Gold Books and Panning Supplies
Lode GoldLode gold occurs within the solid rock in which it was deposited. Areas likely to contain valuable lode deposits of gold have been explored so thoroughly that the inexperienced prospector without ample capital has little chance of discovering a new lode worth developing. Most future discoveries of workable lode gold ore probably will result from continued investigations in areas known to be productive in the past. The districts in which such new discoveries of gold may be possible are too numerous to be listed in detail in this pamphlet. Some of the famous districts are: in California, the Alleghany, Sierra City, Grass Valley, and Nevada City districts, and the Mother Lode belt; in Colorado, the Cripple Creek, Telluride, Silverton, and Ouray districts; in Nevada, the Goldfield, Tonopah, and Comstock districts; in South Dakota, the Lead district in the Black Hills; and in Alaska, the Juneau and Fairbanks districts. Deposits in these districts generally are gold-quartz lodes. Lode Gold Areas Have Been Thoroughly ProspectedProspecting for lode deposits of gold is not the relatively simple task it once was because most outcrops or exposures of mineralized rock have been examined and sampled. Today's prospector must examine not only these exposures, but also broken rock on mine dumps and exposures of mineralized rock in accessible mine workings. Undiscovered Gold is Finely DisseminatedGold, if present, may not be visible in the rock, and detection will depend on the results of laboratory analyses. Usually, samples of 3 to 5 pounds of representative mineralized rock will be sent to a commercial analytical laboratory or assay office for assay. Obviously, knowledge about the geological nature of gold deposits and particularly of the rocks and deposits in the area of interest will aid the prospector. Sources of Gold InformationThere are many publications of interest to those seeking more information about gold. The United States Geological Survey has published lots of reports about general geology and mineral resources for most of the major gold-producing areas. In addition most state geological surveys where gold production has occurred have compiled reports and maps to document the general geology, deposits and mining activity. There are also lots of prospecting guides and maps geared to amateur prospectors. | | 
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