The effect of saltwater on the gold treasures of sunken ships is an exciting story that combines myths with harsh scientific reality. In short: gold itself is almost unaffected by saltwater, but everything around it is destroyed fundamentally. Let's delve into this in more detail. 1. Gold: "The King" is not afraid of water Gold is a noble metal. This is a scientific term that means it is extremely inert and does not react with most chemical elements. Salt resistance: Chloride sodium (salt) and dissolved oxygen in water do not have any corrosive effect on gold. Nothing happens to it that we call "rust" or "oxidation". Appearance: A gold coin or ingot that has been lying at the bottom of the ocean for 300 years will look almost the same as on the day of the shipwreck. It is enough to rinse them with fresh water, and they will shine with their original brilliance. This is why gold has been and remains a symbol of eternal value. 2. What about the "treasures"? Main threats The problem is not with gold, but with its "neighbors" and storage conditions. Threat #1: Electrolytic corrosion (Galvanic couple) This is the biggest and most interesting problem. When different metals are in contact in an electrolyte (and seawater is an excellent electrolyte), an electric current is generated between them. How it works: More "active" metal (anode) begins to degrade, sacrificing itself for the protection of the more "noble" metal (cathode). Example: If a gold coin was lying in an iron chest or next to silver coins and copper cannons, a galvanic couple is formed. Iron and copper will actively corrode, while gold will remain intact. However, the result will be that gold objects can literally "weld" to their neighbors with a spattered layer of rust and minerals. Their extraction becomes a complex archaeological task. Threat #2: Formation of concretions This is a natural "sarcophagus" that forms around objects on the seabed. Process: Soluble salts in water (especially calciu ... Read more