Charm
A small and compact wizardry, normally simple in intent and execution, encoded or embedded into a physical object and fueled by a limited, stand-alone power source or routine. Also, the object in which such a wizardry is embedded.
Charms have an extensive history in worldwide nonwizardly tradition, but they are rarely effective as the users normally do not have the slightest idea how or why they work, and are likely to try to use them for invalid or unethical purposes. Wizards, however, frequently construct charms to hold small pieces of a more complex wizardry in a "ready to go" format. Typical of this kind of use would be the simple charm illustrated here, a cross made of rowan wood bound together by unknotted red string or yarn. The practitioner who designed this charm knew that knotting the string would limit this small spell's effectiveness in terms of energy output, and so has simply used a "five-half wind" which is sufficient to hold the spell in place.
Such encapsulated spell segments can be carried in groups, either independently operating or interrelated -- though it takes some skill to build and organize a charm sequence of this kind so that the charms' energies do not interfere with each other. Nita's charm bracelet is an example of this kind of usage. (TWD et al.)
See also: Amulet: Mnemonic: Physical wizardry: Spell fragment.