This was not done by the U.S. Mint. These coins were plated by private companies for to be sold for profit as collector pieces. Their value is limited to the worth of the metals use to make them plus whatever premium a person may be willing to pay to own them. For a collector of U.S. Mint coins they are considered altered and have no place in such a collection.
Anything with gold content has some value.
None are plated by the US Mint, some may have been plated as novelty coins.
14k F means gold fill not gold plated gold fill is better than plated but not solid gold just a thin layer of gold applied to some other metal
solid gold and silver is more expensive and even heavier. Gold and silver is pretty so being plated gives the same effect.
Yes, there are some custom car shops and a few companies that offer gold plated rims. Theft is a major concern for the onwers of gold rims on any vehicle.
No. All US nickels minted in 1941 contained 75% copper and 25% nickel. If you have one that appears to be made of gold it is probably gold plated or colored with some other substance to give it a gold appearance. Sometimes with nickels that have not been circulated [used in everyday business] tarnish can develop and at times this can give them a golden like appearance depending on the environment they have been in. Also there are chemicals that can be used to create a tarnished look on the uncirculated coin.
In some cases, maybe plated.
No nickel has ever been made of gold. You may have one that has been plated or it may be toned a gold color. Either way it's bad. Gold plating kills the collectible value of any coin. And for buffalo nickels, gold or blue toning means it's been chemically cleaned at some point. Unfortunately it's just a nickel.
Gold plated stuff usually isn't worth sizing. Get some real gold
Most circle earrings are completely sterling silver or sterling silver plated with gold. But some are a base metal, which depends on company, and then plated with gold. Most generally the plated base metal earrings are costume and not very valuable.
Gold necklaces contain the chemical element of gold. This is true if the gold necklace is real gold instead of plated gold. Some gold necklaces are not truly gold.
In chemistry, solid gold is a metallic element. In jewelry, gold may be alloyed with other metals, such as silver: and some "gold jewelry is simply gold-plated.