Stipula Prototype I Castoni Black Roller Ball with Lapis Stone in Clip -- RARE!
Rare! Non-production Stipula I Castoni roller ball. Stipula only made a few of these black pens with an actual Lapis stone on the clip, it appears they were made solely for their distribution network. Stipula produced a lapis on lapis model for production purposes. Another great example of a sought after pen from Stipula's original U.S. distributor. This example also features the original adjustable sleeve that enables the user to regulate the amount of spring on the point...an innovation to try to make a roller ball feel more like a fountain pen. On the cap is a color sticker indicating its prototype status. This is one for the hard core pen collector on your pen list!