In Japan, kagami-mochi are displayed in an alcove on the New Year. On Kagami-biraki they are taken down and eaten. By this time, the kagami-mochi has harden and cracked. It is a good luck charm, so it is not cut with a sharp object rather it is opened by hand or with a hammer. Kagami-biraki means opening the mirror.
Kagami-mochi are two round, flat rice cakes. A large and a small cake are stacked on a stand. Although nowadays this is a traditional decoration, the kagami-mochi was originally an offering to the year god.
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