Geocoin

A geocoin is a metal or wooden coin minted in similar fashion to a medallion, token coin, military challenge coin or wooden nickel, for use in geocaching. The first geocoins were developed by Jon Stanley (aka moun10bike) as a signature item to be placed in caches.

Many of them are made to be trackable on various websites to be able to show the movement around the world and visitors to be able to leave comments when they find the coin.

A geocoin typically has a diameter of 1.5 inches (38 mm) to 2 inches (51 mm) and a thickness between 0.098 inches (2.5 mm) and 0.16 inches (4 mm). Coins with the size of 1 inch (25 mm) are called microcoins, because they fit into microcaches (e.g. film canister). The smallest geocoins with a diameter of 0.5 inches (13 mm) are called nanocoins, and have been sold since 2009. If the diameter is larger than 3 inches (76 mm) the geocoin is called macrocoin, and contains the saying of "that's not a coin it's an anchor".

Personal geocoins are a personal signature item that normally bears the geocacher's handle and personal design. For example, it was Jon Stanley's (aka moun10bike) original manufacture of a coin that started the hobby in the geocaching game. It has a stylized mountain bike and his caching handle, and on the back the geocaching logo.

Geocoins are often minted by caching organizations and companies. Though not specifically a personal signature item they are a form of signature item for the organization that developed them.

Reviewer/Moderator/Lackey Coins are another form of signature items over the years these have their own following. Many of them have taken the time to create their own signature item.

In the first few years the number of coins that were a signature item for a geocaching group, or individuals far outnumbered the coins that were made to sell. However now they tend to be smaller percentage as the industry has a number of coins manufacturers that develop coins for events, holidays, or special coins. The cost to make a personal coin is fairly high.

When a cache listed at geocaching.com contains a geocoin, an icon (often unique to the type of the coin) is shown on the cache page's "Inventory" section. This icon will also appear in the inventory of any cacher holding one as well as in each cacher's historical trackable item listing. Icons will also remain in the inventory of cachers who log the 'discovery' of a geocoin's number without physically removing it from a cache. "Icon collecting" – the act of having these icons listed in one's trackables listing – is an associated hobby. Many people bring geocoins with unique icons to geocaching events so that others may see the coins and use the tracking number to collect the icons online, and it is not uncommon for collectors to activate some or all of the coins in their collections in order to have a matching online collection of icons associated with their geocaching.com accounts.

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Wikipedia