As far as use goes, the paten is placed in the center of the altar and is the focal point of the altar. The paten is used to ritually charge and consecrate items used in magic by placing the items upon it.
As with all magical tools of the witch, non-witches should not touch the paten. If a non-witch touches the paten then the paten needs to be cleansed and re-blessed before it can be used again.
Many modern Wiccans, especially solitary Wiccans who have not been initiated into a coven, do not use a paten. Many Wiccans may not even be aware of this tool. Instead, many Wiccans will wear pentacle jewelry or have some other representation of the pentacle on their altar.
For an image of a patens, click HERE.
Source: modern-wiccan.blogspot.com