Tree Ring Pen with cap made from the stunning bark of Douglas-fir tree. The chronology of these pens spans from the late 1800's or early 1900's to 2016. Tree Ring’s Corteza fountain pens are handmade from Douglas fir trees. The trees are harvested as part of a forest restoration project, which involves thinning unnaturally dense stands of smaller trees to preserve the overall health of older forests. The trees used to make these pens are chosen specifically for the appearance of their growth rings. Each pen is engraved with the years that each tree was born and felled, and this drop features the first Corteza pens made from trees harvested in 2016.