(sold) This is a vintage Blue Diamond Parker Vacumatic Major with a two-tone Fine nib. The pen has been restored, which included a thorough cleaning, an overhaul of the filling mechanism, ink flow adjustment, nib tuning, and a gentle hand polish.
The Golden Pearl Vacumatic is perhaps the most recognizable model of the famous Parker design. The Blue Diamond indicated lifetime warranty, which Parker had respected and heavily promoted in its advertising campaigns, until the company was forced by the US Government to rescind the warranty program. What's important for us today, is that Blue Diamond Vacumatics are typically nicer pens, with larger, higher-quality nibs, and they hold more value among collectors.
The nib is a gorgeous, 14k gold, two-tone nib (platinum masked) that writes a true-to-size Fine line. It has ample tipping material, and of excellent geometry. Parker Vacumatic nibs are unique in how they feel on paper. While most major brand vintage gold nibs feel soft, the Vacumatic nibs are softer still. It's not in terms of flexibility, but, rather, in the nib's ability to smooth out the perception of roughness in the paper, in making the nib feel more connected to the paper in a satisfying manner, one that only a well-tuned vintage fountain pen can provide. The nib writes under very light pressure, but if you want to press a little harder, it will take it, increasing line width and ink flow intensity a bit, giving you a hint of line variation. However, I'd caution against bearing down on the nib too hard, as you are likely to spring it.
Cosmetically, the Golden Pearl celluloid is simply beautiful. It's gleaming, shimmering, full of chatoyancy in ways that only celluloid can. There are no flaws or defects, only faint surface wear. The gold-filled trim is in equally good condition. By the way, the phrase comes from an old penmanship book.