Cartier Diamond PenRARE Diamond Cartier Pen, can be converted to fountain pen. GORGEOUS! Very fine and exceptionally rare diamond and 18k gold fountain pen from the "Louis Cartier" collection, by Cartier. Limited edition of 10 pieces believed to be in existence today. Approx. 18. 0 22. 0 carats of very high grade round brilliant cut diamonds pave set on the barrel of the pen, diamonds are all original and factory set. Comes with box