Montblanc Writers Series Agatha Christie Limited Edition Fountain Pen The design of the Writers Edition created in honour of Agatha Christie is based on the classic style of the early 1920s. Around the cap, made of black precious resin, winds a snake made of 925 sterling silver, which hints at the creeping tension of the author’s novels and also serves as the clip of the pen. The eyes of the snake are set with two rubies that glint bewitchingly. The head of the snake is also engraved on the rhodium-plated 18-karat gold nib. Each Agatha Christie Writers Edition pen is also decorated with the signature of the grande dame of the crime novel. Launched in 1993, the Montblanc Agatha Christie series is limited to 23,000 fountain pens, 18,000 ballpoint pens and 7,000 sets.