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through January 4th, 2026, reopening Monday, January 5th, 2026.
Orders received after 10:30 AM Central Time on Tuesday, December 23rd, 2025, will ship after we return.
DC10440
Price: FREE
When an oblong, boat-shaped object—known as a celt, rattleback or wobblestone—is rotated about its vertical axis in a particular direction, it will stop rotating, begin oscillating, and then spin in the opposite direction. Here’s how to construct your own mysterious celt from an ordinary spoon.