Silverware, protection

Rhodium is used as an alloy with platinum, and as a catalyst. It is also used as a corrosion-resistant electroplate for protecting silverware from tarnishing, for making high-reflectivity mirrors for cinema projectors, and searchlights. It can be used as a catalyst for chemical reactions, and in jewelry. In fact, rhodium is a very common plating for inexpensive jewelry because it is extremely shiny and tarnish resistant. It is actually a very expensive metal however, only need a microscopically thin layer is needed. 

Other important considerations must be taken into account when formulating LADDs. Because of the corrosiveness of typical LADDs, ingredients must be added which protect both the machine itself and fine items such as china and silverware. Generally, silicate is added for this purpose, but its inherent alkalinity in aqueous solutions is not always desired. In Table 9.12 several patents are listed which describe other anticorrosion agents. 

In normal atmospheric exposure, copper forms a layer of copper carbonate (CUCO3), a green substance also called patina, that protects the metal underneath from further corrosion. Likewise, silverware that comes into contact with foodstuffs develops a layer of silver sulfide (Ag2S). 

Jewelry and silverware. Because of its high reflectivity, sterling silver (i.e., a silver-copper alloy) is extensively used for jewelry, silverware, and tableware where appearance is paramount. Sometimes, a protective rhodium coating is electrodeposited onto thin nickel-plated silver objects to avoid tarnishing. Sterling-silver alloy contains roughly 92.5 wt.% Ag, the remainder being copper or some other metals. 

Most intruders are looking for portable and easily saleable items such as DVD players, television sets, home computers, jewellery, cameras, silverware, money, cheque books or credit cards. The Home Office has stated that only 7% of homes are sufficiently protected against Intruders, although 75% of householders believe they are secure. Taking the simplest precautions will reduce the risk, while installing a security system can greatly reduce the risk of a successful burglary. 

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