Geocoins are specially minted coins designed by geocachers and traded and collected. In some regions, geocoins of any type are very rare. Most are collectable.
Among the most sought after are Moun10bike geocoins, which are the first ones.
Most geocoins are trackable on various websites. Anyone can design their own and have it trackable on the Geocaching.com website, at a tracking cost of $1.50 per coin and a $150 icon fee (for coin orders over 250). The minimum limit for an icon and coin name is 250 coins. More and more people are starting to have their own coins minted and tracked.
- Geocoin FAQ (Geocaching.com)