Unknown meaning of a carving on the back of a Buddha statue (Character identified: 朱)
It's 朱

In 篆文: 


It is a common surname in Chinese, originally refers to inner red wood.


  說文解字注: 朱本木名。引伸假借爲純赤之字。糸部曰。絑、純赤也。是其本字也。


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