L380xW100xD20mm, China

This was an opium scale, I believed that this is only a bolder name for a scale of measuring items that are small and expensive (precious was the original choice of word but would be a wrong one if this were indeed an opium scale). The scale packed neatly into a custom carved out wooden case with the pivot rod is made out of elephant bone.
For how a Chinese scale works, please see the earlier post Scale which fits in a bamboo case.