Adjustable "rise and fall" suspension, opaline and porcelain rise and fall

Wow effect guaranteed for this very beautiful suspension adjustable in height thanks to a system of pulleys and a counterweight (in porcelain, filled with lead plate) that we call "raise and lower". The lampshade is rare, it is the first time that I see one of this type, in white opaline with a wavy edge of emerald green color. The pulleys, weights and canopy are in white porcelain, the claw in gilded metal, the electric wire with fabric covering. The socket is intended for bayonet bulbs. This suspension dates from the first half of the 20th century, except for the electric wire which seems to have been replaced a few years ago. The whole is in good general condition, the lamp works, I tested it, no cracks or chips on the lampshade or the porcelain parts. But obviously, this lamp has some signs that testify to its age and its previous lives: the metal making up the claw is patinated, the metal parts on the pulleys have corrosion that has stained the porcelain pulleys (I have started to remove it, you will need elbow grease and fine steel wool to continue the work if you wish), stains on the fabric covering of the electric wire, one pulley has a small missing part but given where it is placed, it can only be original, some light marks on the lampshade at the location for the claw. The lampshade measures 25 cm in diameter.