Discovery Shows Ancient Chinese Used Jewelry Machinery

Discovery Shows Ancient Chinese Used Jewelry Machinery
Scientists believe they have discovered proof that ancient Chinese craftsmen were using complex machinery to work jewelry long before such machines were previously believed to have been invented.

The earliest known historical references to compound machines come from writings attributed to Hero of Alexandria that are dated to the first century AD, but spiral grooves on 2,550-year-old jade rings must have been made by a precision "compound" machine, according to Dr. Peter Lu of Harvard University.

Carved decorations on jade from ancient China were thought to have been made by hand or with simple machines that worked with a single movement. But ornamental jade burial rings reported in Science magazine that date from 771 to 475 BCE excavated from hoards and tombs belonging to ancient officials and nobles indicate that machinery was used.

The jade was worked with compound machines - two or more machines with different motions linked together to perform precision work.

The machine that carved the grooves would have linked rotational and linear motion, perhaps using a stylus suspended over a rotating turntable, says Dr. Lu.