14K Gold Rod And Sterling Silver Rope Bangle With Black Onyx Studded Ends, Weighing 18 Grams. 14K Gold Tested And Silver Tested. Estimated more than 50 yrs old. Gold, Tested Positive using Nitric Acid Chemical Scratch Test, Cloth Rub Test, and Magnet Test. Karat Stamp Markings. The reason Gold needs to be combined with other metals is that it is very difficult to make great designs with just pure Gold, which is very soft and malleable. Gold resists attack by individual acids, but a mixture of nitric acid and hydrochloric acid can dissolve it. It is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to refine gold and to confirm the presence of gold in metallic objects. Gold is a precious metal used for coinage, jewelry, and other arts throughout recorded history. In the past, a gold standard was often implemented as a monetary policy within and between nations, but gold coins ceased to be minted as a circulating currency in the 1930s, and the world gold standard was abandoned for a fiat currency system after 1976. The historical value of gold was rooted in its relative rarity, easy handling and minting, easy smelting and fabrication, resistance to corrosion and other chemical reactions, and distinctive color. Many countries do not require their precious metal items to be stamped and therefore we test to ensure we accurately represent the product. For Size And Weight See The Last Photo If Not Written In This Description. All Photos Represent The Lot Condition. Please Read Our Terms And Conditions.