Psychometry is a psychic skill and is also known as object reading, it is the ability to tune in and pick up on residual energy. Residual energy is a stored energy such as in the atmosphere, buildings and objects, it's like a recorded energy of all things that have happened in the past rather like a video or tape recording.
Any objects can be read even the walls of a house, some people who use psychometry prefer using metal objects, such as watches, necklaces and most commonly keys, the reasons they give for this is that metal tends to store energy better, but in my experience anything can be read even water. Sometimes even a hands on healer can pick up information coming from the person who is receiving the healing, thus in affect reading the person using psychometry.
If you are just starting to develop you psychic abilities, to which I add we can all do. Psychometry is a good place to start, as it stimulates your psychic senses.