We have been Gem Bijou’s clients for over a decade. Over the years we have referred friends to Gem Bijou, who have all been very satisfied with their personalized care. We recently got new batteries for 3 Cartier vintage clocks from Gem Bijou. Unfortunately, the clocks did not work. We then took the clocks to Cartier as we have worldwide lifetime warranties. Cartier advised us that the clocks needed a new battery and “dried out watch oil in the movement.” We believed Cartier's statement resembled Tesla needing an oil change. The Cartier clocks are quartz. We believe that you cannot oil quartz clocks. We double-checked with Sam at Gem Bijou. He confirmed that you cannot oil quartz clocks. We then double-checked it with Bvlgari and got the same answer. Cartier is now repairing the clocks under worldwide warranties. Thank you Sam for helping us to address this discrepancy with Cartier!