We often get e-mails about people finding coins which they think are worth tens of thousands of dollars, but we end up having to disappoint them because they've misidentified the coin as a proof strike or failed to consider the condition. This guide will therefore serve as a quick introduction to the topic of coin valuations.
There are several factors that need to be considered when valuing coins, the first is the coin type or series, then the year, then the variety and strike type, and finally the condition. For all characteristics other than the condition, there is a separate entry on this site and so it's important to correctly identify your coin before assessing its condition.
The series of a coin represents some major distinguishing factor from other coins - this is something not easily confused such as different denominations, changes associated with change in monarch, or for most Commonwealth coinage over the past 75 odd years, a change in the monarch's effigy used.
The next consideration is the year on the coin, coins of different years may be worth vastly different amounts and older is not necessarily more valuable. Generally this is due to differing rarity between years which can be due to many factors. For example coins struck during The Great Depression are often scarce because of a decrease need for coinage during the period due to both decreased consumption and the surplus of coinage struck during the roaring twenties.
Varieties can represent any small difference between coin types such as the presence of a mintmark, which is a letter, dot or small change which indicates where the coin is struck, a specific die used which happens to be rare such as when proof dies are re-used for circulation strikes.
Then there is the strike type, aside from general circulation strikes, there are proof strikes, which are coins specifically struck to the highest standards of the mint, or general special strikes such as coins struck in some special way for some specific purpose. The latter two, when professionally graded, receive the prefix PR/PF or SP respectively. Early proof coins struck for dignitaries can be extremely rare and consequently very valuable and may otherwise look very similar to the general circulation issues, so this is a common point of confusion. Differentiating between proof strikes and circulation strikes varies per issue so you should either refer to the specific article on this site which shows how to differentiate them, or if unclear or not available, use our paid photo-based valuation service.
Grading coins is a complex topic which will be covered in a separate article but the basic gist of it is, the closer a coin is to its as-struck condition, the higher grade it is. The scale is from 1-70 with some suffixes applied which may increase the value of the coin such as Red/Red-Brown/Brown for copper coins, or Deep-Cameo/Cameo for frosted proof coins. Once professionally certified you will receive such a grading for your coin and you can precisely value your coin with this website.
The two major grading services are PCGS and NGC. ANACS also has a good reputation within the US but is not very popular anymore and so ANACS graded coins often sell at a discount. Coins graded by other services are worth significantly less. Beware of coins graded by services with similar sounding names, often disreputable companies will create their grading services with similar names and holders to trick new collectors into using their service.
When choosing which service is better it's best to look at the past sales of the coin. You can do this on this site without a subscription (you just won't be able to see the sale price). It's best to send it to the service which most commonly grades the coin which tends to vary by country. With a subscription, you can also see which service gets the best prices for identically graded coins as this can differ between coins though again usually differs by country.
Because coin grading measures how close a coin is to its original condition, it is impossible to increase the grade of a coin through cleaning and this will almost certainly reduce the grade of a coin. That being said, sometimes some forms of cleaning may make it easier or even possible to grade a coin such as the removal of foreign material from the surface of a coin. This, when done professionally, can often be done without damaging the coin. Other times cleaning can be done to prevent further damage, such as to remove corrosive material from a coin. This is often done even though it may damage the coin because it can prevent further damage from occurring.
Coins that have been improperly cleaned destroying the original surface of the coin are worth significantly less and most reputable grading services will not grade these.
So the first step is to use the search box in the top-right of this page on desktop or within the top menu on mobile to identify your coin, then either use one of the many grading guides on the web to estimate your coin's grade or use our paid photo-based valuation service, then use this estimation to see whether it's worth getting your coin professionally graded. Once professionally graded you will be able to sell your coin quite easily - at that stage it may be worth getting a higher level subscription to see wholesale values to see what is a fair price for your coin.