Black & Pearl -  Oversize and Standard Size Pens - This is one of the hardest colors to find in the Enduras. They are virtually always found with discoloration. These show the typical darkening to the barrel of the pen. Discoloration to the cap is not as much of a problem as the barrel. The color change is caused by a chemical reaction between the ink sac and the plastic that was used to make the pens. It occurs even in pens that have never had ink in them. Click on the picture for a much larger image.