About This Pen: This Montblanc Solitaire Doue Geomtric Dimension M23799 Pen has a fountain pen writing system with piston converter (allows optional use of ink cartridge). It features a black precious resin barrel, complemented by a champagne-tone gold-plated cap with three-dimensional geometric pattern. Both clip and fittings are platinum-plated. The three champagne-tone gold-plated rings on the cap is embossed with the Montblanc brand name. The nib is made out of 18K champagne-tone gold and is hand-crafted by Montblanc.