Antique silver antique private transactions Chronicles free appraisal auction

Silver, refers to silver coins, with a universal value of the collection, with "Yuan bulk" as the representative. From the perspective of coin collection does not recommend the silver surface black oxide layer (also known as "package pulp") cleared away. This silver coin is easy to damage the surface, but also affect collectible coin. With good patina of silver is often sought after Friends of Tibet, even several times the price of a new uncirculated version. In addition, wipe with a toothbrush dipped in toothpaste to clean silver can indeed approach oxide layer, but be sure to use a soft-bristled, otherwise silver will undoubtedly damage. This method is difficult to do right, it is not recommended. Also, it can clean with a low concentration of the acidic liquid. This method is also the risk of damage of silver. Chemical acid to be very familiar with the job. Chemical reactions: save the same kind of conditions are the same coin, but the results will have a different, and some have cured patina, but some do not. This is with the silver production process to some extent. Silver's patina on the edge of total originated and gradually inward (although not all, but most of all the case). Including the new Chinese coins (a plastic box with or without plastic box), old silver dollar (no box) oxide, many are starting from the circumferential edge, have less divergent from silver center. Why? New China silver patina, often a common silver-sided oxidation obviously, the other side of minor or no oxidation conditions. And silver placed, coins and boxes gap density could be. New China silver, easily oxidized sulfide 999 silver, 999 silver coins relatively non-much less (usually only a hint of brown oxide or chloride fog); old silver dollar, although not 999 silver sulfide, there are many colorful . Why is this? Silver oxide and chloride, previously was said to be light because the microorganisms and the like, mint scientific studies show that the main reason, or chemical, followed by the physical form of the constraints and coinage technology. Effects of UV on the silver surface corrosion compound for further study. If the spherical silver body floating suspension lines placed in a sealed box to avoid pressure, water vapor stratification, light and other factors, oxidation what was the result? Where each part begins to oxidize it first? (When I was in high school, he thought: a spherical magnet completely regular, positive and negative in what?) Had complained about the Friends of Tibet will be oxidized NGC coins boxing box, in fact, in front of boxing, graders are exposed silver was observed, when the state did not reveal bare environment and the currency before leaving the factory also has great relevance, not necessarily the rating box problem. Mint mold surface and some to be oiled, some coins die casting chapter also stained with oil; some coins chapter is to be done after a good pressure oxidation treatment, there are films. Oil, chemical film, has remained untouched, it will more or less affect the product surface effects N years later. Early large-sized silver coins, seals intact, is no circular plastic boxes, direct seal, plastic factory in the chemical composition and film, etc., will affect the currency side, such as: Sun Yat-sen in 1986, five ounces of silver and so on. Whether the old or the new Chinese silver dollar coin, its color is not all "bad", according to the color of the different results, some popular, its value is not higher than the color of money, for example: there are beautiful colors silver sulfide. Such is more emphasis on foreign currency, and many collectors regarded as rare treasures. On some new China early coins, occasionally black specks, especially non-small size of 999 sterling silver, is suspected coinage process tainted credits surface caused by impurities of iron.