Both variants are original. Montblanc traditionally delivers writing instruments for the French and Swiss markets with 18kt nibs, since French law only speaks of "gold" from 750/1000 gold content; in the rest of the market, 14kt nibs (585) are fitted. For the respective variants, Montblanc has different ID numbers. Since Montblanc writing instruments are internally identified primarily via the clip-ring numbers, it can also happen with a mix-up that, e.g., the body of a Solitaire Doué (with 18kt nib) is combined with other components. Montblanc customer service is sometimes not informed about this 18kt variant and wrongly classifies such pieces as fakes.