Scottish Rite Masonic Museum & Library

Masonic Spinner Watch Fob. Gold-tone Masonic spinner watch fob. A loop at the top is attached to a semi-circle frame. Suspended from the frame by pins is a disk. Each side of the disk has part of a square and compass with G in the middle (all in blue) in the center. When the disk is spun rapidly, the parts of the symbol on both sides appear as a complete symbol, by optical illusion.

When spun quickly, the circular part of this fob creates an optical illusion: a common Masonic symbol—a blue letter G within a square and compasses—becomes visible.