An item generally round in shape and usually having a centrally located hole. It has at least one flat bearing surface. It is made of precious or semi-precious gem (ruby, sapphire and the like), natural or synthetic. It is intended for use in precision instruments, meters, timing devices, clocks, and the like.
jewel part name assigned by controlling agency, used with screws 20000740, 20000687, and plate assy 400193 special features, aircraft mechanical clock 6645-00-076-3050 end item identification, to 5n11-2-11-33 reference data and literature