Parker Duofold MK I International Green Marble Fountain PenThe Parker Duofold Green Marble Fountain Pen is a high end writing instrument that is part of Parker's Duofold collection. Produced around 1988. The pen features a green marble design on its barrel and cap, which is created by layering different shades of green resin to create a unique marbled effect. The Marbled Acrylic elements are offset with a gold Trim. The pen also features the classic Parker arrow clip, which adds to its elegant appearance. .