20 Facts About the Chemical Element Silver

20 Facts About the Chemical Element Silver Silver is a precious metal that has been known since ancient time. This is a list of interesting facts about the element silver. 1. The word silver comes from the  Anglo-Saxon word  seolfor.  There is no word that rhymes with the English word silver. It is a transition metal element, with symbol Ag, atomic number 47, and atomic weight of 107.8682. 2. Silver is exceptionally shiny! It is the most reflective element, which makes it useful in mirrors, telescopes, microscopes and solar cells. Polished silver reflects 95% of the visible light spectrum. However, silver is a poor reflector of ultraviolet light. Stocktrek Images/Getty Images 3. Silver can exist in its native state. In other words, nuggets or crystals of pure silver exist in nature. Silver also occurs as a natural alloy with gold that is called electrum. Silver commonly occurs in copper, lead, and zinc ores. 4. Silver metal is not toxic to humans. In fact, it can be used as a food decoration. However, most silver salts are toxic. Silver is germicidal, meaning it kills bacteria and other lower organisms. 5. Silver is the best electric conductor of the elements. It is used as the standard by which other conductors are measured. On a scale of  0 to 100, silver ranks 100 in terms of electrical conductivity. Copper ranks 97 and gold ranks 76. 6. Silver has been known since antiquity. It was one of the first five metals to be discovered. Mankind learned to separate silver from lead back in 3000 BC. Silver  objects have been found dating back before 4000 BC. It is believed the element was discovered around 5000 BC. Early Saxon coins, 5th-6th century. Silver pennies known as sceattas, found in excavations in London area.   Heritage Spanish/Getty Images 7. Only gold is more ductile than silver. An ounce of silver can be drawn into a wire 8,000 feet long. 8. The most commonly encountered form of silver is sterling silver. Sterling silver consists of 92.5% silver, with the balance consists of other metals, usually copper. 9. The chemical symbol for silver, Ag, comes from the  Latin word for silver, argentum, which in turn derives from the Sanskit word  argunas, which mean shining. 10. A single grain of silver (~65 mg) can be pressed into a sheet 150 times thinner than the average sheet of paper. 11. Silver is the best thermal conductor of any metal. The lines you see in the rear window of a car consist of silver, used to defrost ice in the winter. 12. The words for silver and money are the same in fourteen languages or more. 13. The primary source of silver today is the New World. Mexico is the leading producer, followed by Peru. The United States, Canada, Russia, and Australia also produce silver.  Around two-thirds of the silver obtained today is a by-product of copper, lead, and zinc mining. Silver mines in Mexico, such as this now-abandoned one, provided Spain, in the 18th century, with over one third of the silver sent out of the New World.   Danny Lehman/Getty Images 14. Coins minted in the United States prior to 1965 consists of about 90% silver. Kennedy half dollars  minted in the United States  between 1965 to 1969 contained 40% silver.   15. The compound silver iodide has been used for cloud seeding, to cause clouds to produce rain and try to control hurricanes. 16. The price of silver presently is less than that of gold, varying according to demand, discovery of sources and the invention of methods of separating the metal from other elements. In ancient Egypt and Medieval European countries, silver was valued more highly than gold. 17. Some silver compounds are highly explosive. Examples include silver fulminate, silver azide, silver(II) oxide, silver amide, silver acetylide, and silver oxalate. These are compounds in which silver forms a bond with nitrogen or oxygen. Although heat, drying, or pressure often ignite these compounds, sometimes all it takes is exposure to light. They may even explode spontaneously. 18. Silvers atomic number is 47, with an atomic weight of 107.8682. 19. Silver is stable in oxygen and water, but it  tarnishes in air because of a reaction with sulfur compounds to form a black sulfide layer. 20. Uses of silver metal include currency, silverware, jewelry, and dentistry. Its antimicrobial properties make it useful for air conditioning and water filtration. It is used to make mirror coatings, for solar energy applications, in electronics, and for photography. Sources Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0-08-037941-9.Hammond, C. R. (2004). The Elements, in Handbook of Chemistry and Physics (81st ed.). CRC press. ISBN 978-0-8493-0485-9.Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.

10 Ways to Maximize Research at the Courthouse or Archives

10 Ways to Maximize Research at the Courthouse or Archives The process of researching your family tree will eventually lead you to a courthouse, library, archives or other repository of original documents and published sources. The day-to-day joys and hardships of your ancestors’ lives can often be found documented among the numerous original records of the local court, while the library may contain a wealth of information on their community, neighbors and friends. Marriage certificates, family histories, land grants, military rosters and a wealth of other genealogical clues are tucked away in folders, boxes, and books just waiting to be discovered. Before heading for the courthouse or library, however, it helps to prepare. Try these 10 tips for planning your visit and maximizing your results. 1. Scout the Location The first, and most important, step in onsite genealogy research is learning which government most likely had jurisdiction over the area in which your ancestors lived during the time they lived there. In many places, especially in the United States, this is the county or county equivalent (e.g. parish, shire). In other areas, the records may be found housed in town halls, probate districts or other jurisdictional authorities. Youll also have to bone up on changing political and geographical boundaries to know who actually had jurisdiction over the area where your ancestor lived for the time period youre researching, and who has current possession of those records. If your ancestors lived near the county line, you may find them documented among the records of the adjoining county. While a bit uncommon, I actually have an ancestor whose land straddled the county lines of three counties, making it necessary for me to routinely check the records of all three counties (and their parent co unties!) when researching that particular family. 2. Who Has the Records? Many of the records youll need, from vital records to land transactions, are likely to be found at the local courthouse. In some cases, however, the older records may have been transferred to a state archives, local historical society, or other repository. Check with members of the local genealogical society, at the local library, or online through resources such as the Family History Research Wiki or GenWeb  to learn where the records for your location and time period of interest might be found. Even within the courthouse, different offices usually hold different types of records, and may maintain different hours and even be located in different buildings. Some records may also be available in multiple locations, as well, in microfilm or printed form. For U.S. research, The Handybook for Genealogists or Red Book: American State, County and Town Sources, both include state-by-state and county-by-county lists of which offices hold which records. You may also want to explore WPA Hist orical Records Survey inventories, if available for your locality, to identify other potential records. 3. Are the Records Available? You dont want to plan a trip halfway across the country only to find that the records you seek were destroyed in a courthouse fire in 1865. Or that the office stores the marriage records in an offsite location, and they need to be requested in advance of your visit. Or that some of the county record books are being repaired, microfilmed, or are otherwise temporarily unavailable. Once youve determined the repository and records you plan to research, it is definitely worth the time to call to make sure the records are available for research. If the original record you seek is no longer extant, check the Family History Library Catalog to see if the record is available on microfilm. When I was told by a North Carolina county deed office that Deed Book A had been missing for some time, I was still able to access a microfilmed copy of the book through my local Family History Center. 4. Create a Research Plan As you enter the doors of a courthouse or library, its tempting to want to jump into everything at once. There usually arent enough hours in the day, however, to research all records for all of your ancestors in one short trip. Plan your research before you go, and youll be less tempted by distractions and less likely to miss important details. Create a checklist with names, dates and details for each record you plan to research in advance of your visit, and then check them off as you go. By focusing your search on just a few ancestors or a few record types, youll be more likely to achieve your research goals. 5. Time Your Trip Before you visit, you should always contact the courthouse, library or archives to see if there are any access restrictions or closures which may affect your visit. Even if their website includes operating hours and holiday closures, it is still best to confirm this in person. Ask if there are any limits on the number of researchers, if you have to sign up in advance for microfilm readers, or if any courthouse offices or special library collections maintain separate hours. It also helps to ask if there are certain times which are less busy than others. Next 5 More Tips for Your Courthouse Visit Research Tips 1-5 6. Learn the Lay of the Land Each genealogical repository you visit is going to be slightly different - whether its a different layout or setup, different policies and procedures, different equipment, or a different organizational system. Check the facilitys website, or with other genealogists who utilize the facility, and familiarize yourself with the research process and procedures before you go. Check the card catalog online, if it is available, and compile a list of the records you want to research, along with their call numbers. Ask if there is a reference librarian who specializes in your specific area of interest, and learn what hours he/she will be working. If records youll be researching use a certain type of index system, such as the Russell Index, then it helps to familiarize yourself with it before you go. 7. Prepare for Your Visit Courthouse offices are often small and cramped, so it is best to keep your belongings to a minimum. Pack a single bag with a notepad, pencils, coins for the photocopier and parking, your research plan and checklist, a brief summary of what you already know about the family, and a camera (if allowed). If you plan to take a laptop computer, make sure that you have a charged battery, because many repositories do not provide electrical access (some do not allow laptops). Wear comfortable, flat shoes, as many courthouses don’t offer tables and chairs, and you may spend a lot of time on your feet. 8. Be Courteous Respectful Staff members at archives, courthouses and libraries are generally very helpful, friendly people, but they are also very busy trying to do their job. Respect their time and avoid pestering them with questions not specifically related to research in the facility or hold them hostage with tales about your ancestors. If you have a genealogy how-to question or trouble reading a particular word that just cant wait, it is usually better to ask another researcher (just dont pester them with multiple questions either). Archivists also greatly appreciate researchers who refrain from requesting records or copies just before closing time! 9. Take Good Notes Make Plenty of Copies While you may take the time to reach a few on-site conclusions about the records you find, it is usually best to take everything home with you where you have more time to examine it thoroughly for every last detail. Make photocopies of everything, if possible. If copies arent an option, then take the time to make a transcription or abstract, including misspellings. On each photocopy, make note of the complete source for the document. If you have time, and money for copies, it can also be helpful to make copies of the complete index for your surname(s) of interest for certain records, such as marriages or deeds. One of them may later make an appearance in your research 10. Concentrate on the Unique Unless the facility is one you can easily access on a regular basis, it is often beneficial to begin your research with the parts of its collection that arent easily available elsewhere. Concentrate on original records that havent been microfilmed, family papers, photograph collections, and other unique resources. At the Family History Library in Salt Lake City, for example, many researchers begin with the books as they are generally not available on loan, while the microfilms can be borrowed through your local Family History Center, or sometimes viewed online. Sources Eichholz, Alice (Editor). Red Book: American State, County Town Sources. 3rd Revised edition, Ancestry Publishing, June 1, 2004. Hansen, Holly (Editor). The Handybook for Genealogists: United States of America. 11th Edition, Revised edition, Everton Pub, February 28, 2006.