Precious metals primarily include gold and silver, but may also include platinum and paladium as well as other exotic metals and alloys of these metals. Lately, due to the high metal costs, there are a lot of ads for buying and selling precious metals. Primarily, many companies have 'appeared' willing to purchase your gold from you. There are a few things that you should know if you want to buy or sell your precious metals.
Gold is rarely pure unless you have gold bullion in the form of bars, ingots or coins. Gold bullion will almost always include a declaration of purity as well as a weight, usually in troy ounces. Gold purity is expressed either in terms of karats or in terms of percentage purity. Don't confuse karat, a measure of purity, with carat a measure of mass, used primarily with precious stones. Karat purity is measured on a scale from 0 to 24 karats where 24 karat is 99.99% pure gold and 18 karat gold is 18/24 or 75% pure gold. The remaining material is an alloy, often silver. Gold jewellery is commonly 14k or 18k. When selling gold jewellery you must be aware that you will only receive value for the pure gold in your piece. A 12 gram 14k gold ring contains a maximum of 7 grams of gold. It is unlikely that any value will be ascribed to the remaining 5 grams of alloy. As a word to the wise, an item marked as "gold filled" or "HGE", which stands for "Heavy Gold Electroplate" is actually gold plated. These items may have intrinsic value, but there is no value in the gold content. Do not be fooled into thinking that you are purchasing them for their gold content.
Coloured gold such as white or pink or rose gold is merely gold with a coloured alloy. This clearly means that you will never find 24 karat white or pink gold. White gold is alloyed with Palladium, Nickel or Manganese and is often plated with Rhodium for additional shine and wear resistance. In addition, the alloys often leave a coloured tinge or hue to the piece which the Rhodium plating helps obscure.
Pink or rose gold is gold alloyed with copper and sometimes copper and silver. If zinc is also added, the colour can be changed to a reddish-yellow.
Purity, when expressed as a percentage is usually in the millesimal fineness format. The system is based upon parts per thousand so a 999 fine gold would be 999/1000 or 99.9% pure. This system is sometimes abbreviated as four 9's or five 9's denoting 99.99% or 99.999% pure respectively. The purest readily available gold is currently five 9's although six 9's may have been produced by the Perth mint in 1957. The Royal Canadian Mint produces collector coins at four and five 9's purity.
Silver is commonly found in bullion, jewellery and even tableware. Silver fineness is commonly expressed in the Millesimal fineness format. Silver bullion is commonly found in three 9's and four 9's fineness. Also commonly seen is Sterling Silver which is 925 or 92.5% pure. Silver plate is very common in tableware and is marked in a variety of different ways. Silver plate has essentially no silver value. The only value is in the intrinsic value of the piece.
Platinum may be found as both bullion and jewellery. When in the form of bullion, the purity is commonly expressed in the Millesimal fineness format. Pure Platinum is seldom more than 995 or 99.5% pure due to refining challenges. Platinum used in jewellery is commonly 950 or 95% pure
Palladium is commonly used as an alloy to produce white gold (sometimes other alloys such as nickel or manganese are also used). When in the form of bullion, the purity is commonly expressed in the Millesimal fineness format. Pure Palladium is commonly marketed at 9995 or 99.95% pure when in bullion format.
Many other metals have significant and volatile values. You should be aware that the purity of these metals can vary drastically and is a significant factor in determining the value.
Coins of North America
Many coins were historically made using precious metals, notably gold and silver. The face value was usually a reflection of the value of the metal contained within the coin. Modern coins are seldom made of precious metals unless they are marketed as collector or bullion coins. Pre-1964 US dimes and quarters contain approximately 90% silver by weight. Pre-1967 Canadian dimes and quarters are at least 80% silver while the same coins from 1968 may only be 50% silver. Selected early years contained up to 92.5% silver. Even nickels were made of silver between 1911 and 1921. Guess they probably didn't call them nickels back then. Modern nickels are no longer made of nickel either. By 1969 there was no silver in circulation currency.