https://www.merriam-webster.com/dictionary/Metonic%20cycle
METONIC CYCLE Definition & Meaning - Merriam-Webster
The meaning of METONIC CYCLE is a period of 19 years after the lapse of which the phases of the moon return to a particular date in the calendar year.
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https://gongs-unlimited.com/collections/oetken-gongs/products/oetken-24-metonic-cycle-moon-gongs
Oetken 24" Metonic Cycle Moon Gongs - Gongs Unlimited
Each handmade Oetken Gong has its own individual range of tonality and feel, all while retaining the quality of the classic style. Add one to your sound...
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