Several features expose such counterfeits very reliably. On the original Solitaire, the cap top is of the same material as the body with only the star at the front, while fakes often show a completely black cap top. The spaces between the cap rings on plagiarisms show recognisable indentations and are black, while on the original the body material shimmers through. Additionally, on a fake LeGrand the thread for screwing on the cap is often missing, which a larger rollerball should actually have. A comparison with pictures on the Montblanc website or relevant collector sites usually suffices to determine the differences.