In
divination, an anachitis, or anancitis,
meaning "stone of necessity" is a stone used to call up spirits from water. It was described as a type of
diamond
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, ...
by Martin Ruland the Elder.
[
The stone was used in classical antiquity by the Magi, being described by Pliny the Elder as one of their "dreadful lies". Its use had fallen out of favour by the Middle Ages.]
References
Divination
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