Leprechauns are hard working. they are particular to the crafts of leather working and cobbling. Leprechauns do possess gold and are wonderful at tricking robbers to protect it. Leprechauns can also be called clurichauns. They spend much of their time in their workshops in the forest, but are known to winter in the people's basements especially if there is food. You know there was a leprechaun living in your cellar if there are empty cans and bottles found in the spring. Leprechauns are also good at making horseshoes and have been known to not only shoe odd animals like goats and cats, but ride them as well. Leprechauns sometimes tell thieves where their gold is hidden and if the thief marks the location like a notch on a tree, then he'll come back later and there will be notches on ALL of the trees. Even if someone was to get a leprechaun's treasure, it would turn to something mundane like leaves or pebbles. Leprechauns sometimes wear little leather pouches carrying "fools gold". Leprechauns never forget when someone has wronged them. This is typical in the faery world.
* photo is courtesy of Arthur Spiderwick's Field Guide