Opus 88 Demo Fountain Pen — Sapphire

Sparkle and Swirl, Captured in Resin

The Opus 88 Demo Sapphire trades pure transparency for something more atmospheric: a body of swirling white, light blue, and dark blue acrylic flecked with shimmer, evoking flowing water caught mid-motion. Clear blue resin finials bookend the design at cap and barrel, letting a hint of the ink level show through even where the body itself turns more opaque. Because of the swirled casting process, no two Sapphire pens are ever quite identical — the pattern you receive is genuinely your own.

Design & Construction

The Sapphire follows the Demo's familiar architecture: a straight-sided, non-postable barrel and cap with a clean, cylindrical silhouette. Capped, the pen measures approximately 147.6 mm; uncapped, approximately 136.5 mm, with a cap length of approximately 63.6 mm. Grip diameter is approximately 11.0 mm, and the pen weighs approximately 27 g — light enough for long writing sessions. A polished chrome clip completes the design. Note that this pen does not post — the cap does not attach to the end of the barrel — so the length you write with is the uncapped length.

The pen ships in an Opus 88 gift box with a glass eyedropper pipette included for filling.

Eyedropper Filling System & Shut-Off Valve

The Sapphire uses a full Japanese-style eyedropper filling system, with the entire barrel functioning as an ink reservoir — capacity runs approximately 3.5 ml, enough for extended writing sessions between fills. An integrated shut-off valve, operated by an ebonite piston and rubber gasket at the base of the barrel, seals the feed off from the barrel when fully closed, reducing the risk of leaks or ink burping — a real advantage for a pen that travels, including by air. Unscrewing the blind cap and loosening the rear rod opens ink flow to the feed for writing; during long writing sessions, leave the valve open to take full advantage of the pen's high capacity.

To fill: unscrew the grip section from the barrel, use the included glass pipette to draw ink, deposit it into the barrel, and reassemble. This pen uses bottled ink only — no cartridges or converters are compatible with this filling system.

Nib Options

The Sapphire is fitted with a black PVD-coated #6 JoWo stainless steel nib (also referred to as the #12 model), available in two variants:

Standard nibs (SKU 23091801):

• Extra Fine (EF)
• Fine (F)
• Medium (M)
• Broad (B)
• 1.5 mm Stub

Flex nibs (SKU 23091902B):

• Flex Extra Fine
• Flex Fine

Opus 88 nibs tend to write slightly broader than equivalent Japanese sizes — if you usually reach for a Pilot or Sailor fine, consider sizing down one step.

Manufacturer Warranty

Opus 88 fountain pens are backed by the manufacturer's warranty against defects. If your pen ever needs attention, bring it to our Gatineau boutique and we will coordinate directly with Opus 88 on your behalf. Full details, eligibility, and delivery options →

At Shosai

The Opus 88 Demo Sapphire is a limited-run colorway and has sold out at several retailers in the past — once our allocation sells out, it's unlikely to be restocked. Available at Shosai's Gatineau boutique and through our online store, serving the Ottawa–Gatineau National Capital Region and fountain pen enthusiasts across Canada. Each pen is inspected before shipping, and because every piece's swirl pattern is unique, we're happy to share photos of your specific pen before it ships if you'd like to see it first. If you have questions about nib selection, ink pairing, or filling an eyedropper pen for the first time, we are here to help.

Bilingual service — English and French.