Black Scrying Mirror
The black scrying mirror is a very old tool that's been used for scrying and divination for a very long time - pretty much ever since glass was invented and the first mirrors made. Often referred to as a scrying mirror rather than a black mirror or black scrying mirror, it is a very useful addition for anyone interested in divination or communication with the spirit world.
Scrying is an unusual method of divination but has been used for centuries. Nostrodamus for instance, made use of scrying for divination purposes. Although scrying was around long before the black mirror, the mirror has now become one of the most popular divination tools - especially for those who are a little more adventurous and wish to try something new.
In the early days the mirror was usually made from concave glass, which is very hard (and outrageously expensive!) to obtain so nowadays it is more commonly made from flat glass. This change from concave to flat does not diminish its properties and capabilities in any way. Flat works just as well as concave.
Mirror scrying is in effect a very old form of crystal gazing. Scrying is often considered one of the most difficult methods of divination for several reasons. Unlike more well known methods of divination such as Tarot cards or runes, scrying can often be much more symbolic and hence somewhat more difficult to interpret. Most often the answer to intepretation lies within you rather than within a "text book" definition.
Although initially it is more difficult to grasp, divination with a scrying mirror is well worth the effort and may well bring you experiences and answers you wouldn't get any other way.