Early 20th cent? I believe this to be a Vietnam highlands shield. Concave on the outer side, convex on the inner side. On the reverse side the handhold riser/spacer are loose, there is a slight wiggle to the handle. It can be picked up by the handle with care. The a section of the bamboo piece on the circumference of the shield needs to be glued down/repaired. There are paint/ lacquer chips, which is to be expected with age and handling.
The diameter is 23 inches.
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