Silver, chemical symbol Ag, one of the precious metals, was often circulated as currency in ancient times and had a high value preservation. Sterling silver, free of impurities, white in color, metallic luster and soft in texture. There are impurities, its color is gray-red, and its texture is hard.
The ancients used to bite it with their teeth when identifying silver. Natural silver often exists in minerals in the form of alloys with metals such as gold, platinum, and copper. Silver has high physical stability, good thermal conductivity and electrical conductivity, and is used in many fields. Electronic and electrical materials: such as electric silver contact switches, silver electrodes, etc. Photosensitive materials: such as X-ray film, printing film, photographic film, electron microscope photographic film, etc. Chemical and chemical materials: such as silver catalyst, electronic electroplating preparation, silver paste, etc. In the medical field, an aqueous solution of silver nitrate, a compound of silver, is commonly used to make eye drops. Various silver tableware in medieval Europe, etc. Various silver objects in the Western Church are endowed with the power to exorcise evil spirits.
Silver can decompose a small amount of silver ions in water, which can adsorb and kill microorganisms in the water. It has a strong bactericidal ability of a few billionths of a milligram of silver and can purify 1KG of water. In ancient my country, silver needles were often used to test poison. It is because arsenic was often used as a poison in ancient times, and arsenic was mixed with sulfur or sulfide. Silver reacts chemically with sulfur to produce a black precipitate. The complex composition of today’s toxic substances makes this method ineffective
Silver itself has strong ductility. One gram of silver can be drawn into filaments two kilometers long. It is often made into various fashionable and fashionable handicrafts and accessories with unique shapes, exquisite craftsmanship, and is divided into jewelry colors and processing methods. Sterling silver, grain silver, coloured silver, cast silver, wrought silver and silver masterwork. Silver jewelry is identified by methods such as color, hardness and elasticity, weight, listening to sound, and reagent testing. Silver is divided into sterling silver: there is a “S925″ or “Ag925″ logo. Pure Silver: It has the logo of “S990″ or “Au990″. Silver Plated: Marked with “SL” or “FS”. Most of the silver jewelry sold on the market is sterling silver jewelry marked with the 925 logo.
Color: The higher the purity of silver jewelry, the whiter the surface color, the higher the gloss, and the 925 mark will be printed on the jewelry. If it contains other metal substances, the color will change. If it contains lead, the surface is blue-gray; if it contains copper, the surface is rough and does not have high gloss.
Weight: The density of silver is 10.49 g/cm. Larger than ordinary metals, as the saying goes, “aluminum is light, silver is heavy, and copper is in the middle”. If the jewelry is large in size and light in weight, it can be preliminarily judged that the jewelry contains other metals.
Hardness: The hardness of silver is 2.7 on the Mohs scale, which is higher than that of lead and tin. lower than copper. Scrape the jewelry with a pin, there are traces but not obvious, it is silver. The traces are clearly prominent and are lead or tin. No trace, it’s copper
Listen to the sound: sterling silver jewelry is inelastic, the faster the rhythm, the louder the sound. Copper, the sound is short, high and sharp; lead or tin has no elasticity, and the sound is dull and short. The price of silver has always been unstable, and the price of silver of different brands is also different, so users still need to take the actual transaction price as the criterion.
Reagent detection: nitric acid is dropped on the filing port of silver jewelry, the color is slightly green, the silver content is high, and the color is dark green and black, the silver content is low.
Egg detection: put silver jewelry in an egg, the one that will turn black after ten seconds is sterling silver
The purity of silver jewelry is different, and the price is also different. The price of sterling silver varies from day to day, rising and falling, so the price is also uncertain. The price of silver jewelry is mainly related to the style and craftsmanship as well as the craftsmanship fee of the brand side.
Sterling silver jewelry is recommended to be worn frequently, as the body’s oils can keep silver its natural luster. In daily life, sulfur soaps, hair dyes, and cosmetics contain sulfur components, and eggs contain hydrogen sulfide, which can react with silver to turn into black silver sulfide. Tap water, dish soap, laundry detergent, and laundry detergent contain bleach, which can corrode silver jewelry and make it tarnish. Seawater and hot spring water are prone to react with silver and should be avoided as much as possible. When not wearing, use flannel bag and jewelry box to prevent oxidation and blackening from contact with air.
When cleaning silver jewelry, you can soak it in cola, overnight tea, and silver washing water. Can be burned. You can also wipe with acetic acid, toothpaste, correction fluid, and silver cloth. A coat of nail polish on silver jewelry can keep silver jewelry from darkening for a while. It should be noted here: silver washing water and fire will corrode the silver surface, making it easy to blacken again in a short time. Caution is recommended.
Post time: Sep-02-2022