TWSBI Diamond 580 Iris Fountain Pen - Clear with plated aluminium trim
Catching the light at the right angle
The TWSBI Diamond 580 Iris Fountain Pen is a full size pen that uses an iridescent trim to catch the light and your eye. It shifts constantly as you move the pen, from blues, through to purples and pinks. Combined with the transparent demonstrator body, this pen feels part precision instrument and part moving object.
A pen that reminds you writing is not a static task.Â
Why you’ll love it
- Iris aluminium trim and nib detail, with colour shifts in changing light
- Transparent demonstrator body, showcases your ink choice
- Faceted barrel design adds an architectural feel to balance the "pretties"
- Excellent for both daily usability and collector appeal
- High ink capacity and easy to pair with any colour ink
Feel in the hand
The clear body still gives you all the mechanical satisfaction TWSBI is known for, but the iris trim changes the emotional appeal. It feels modern and expressive, without becoming loud. But also feels adaptable, as changing the ink colour, makes it feel slightly new each time you refill it.
Who it’s for
- Writers wanting a demonstrator pen with more visual personality
- Fountain pen users ready to move beyond entry level pens
- People who enjoy matching inks to pen aesthetics
- Journalers and sketchers who enjoy the ritual of filling pens
Not for
- Minimalists wanting an understated pen
- Users who prefer opaque resin bodies to hide all the ink
- People who dislike any type of maintenance
Practical tips
- Twsbi pens are designed for easy maintenance. If you spill ink in the pen cap, use an elastic band wrapped along the length of a pencil to remove the inner cap for cleaning
FAQs
Is this beginner-friendly?
Yes, you dial in the ink at a controlled pace, and will be writing for a couple of weeks before you have to refill. The pen box includes filling instructions.
How much ink does it hold?
The chamber can hold up to 1.9mL, which is 2-3 times a cartridge or converter.
How does it compare to Twsbi Eco?
Diamond 580 is the more refined everyday writer with a screw-in nib unit and improved grip section. Eco is simpler and more entry-focused.
What's the difference between 580, 580AL and 580ALR?
580 is the base model. AL adds aluminium parts. ALR adds ribbed grip for extra control.
Can you change nibs?
Yes, for the 580 Iris, TWSBI usually supply the nib and feed on a holder. Remove the original nib unit and move the grip and collar from that unit over to your new nib and feed.
Does it come with ink?
No, bottled ink is required. You can use any bottle ink labelled suitable for fountain pens.
Is it fragile?
Not with normal care. Avoid over-tightening the cap and avoid unnecessary full disassembly.
How do you clean it?
Flush with water through the piston system until clear. Full disassembly is only needed occasionally for long-term maintenance.
What’s included
- TWSBI Diamond 580 Iris Fountain Pen
- Wrench
- Silicone grease
- Presentation box
- Free nib tuning from LarryPOST
Ink pairing suggestions
- Sheening inks for maximum light play
- Deep teals, violets, grey purples
- Petrol blues. We like De Atramentis Pigeon Blue.
Build your practice
- Use with the Twsbi Diamond Ink Well for mess free filling
- Replacement nibs are useful for exploring line widthÂ
- De Atramentis Document ink for permanence
- Twsbi Pipe is an attachment to fill from an almost empty ink bottle
Specifications
- Brand:Â TWSBI
- Brand series:Â Diamond 580
- Launch:Â July 2022
- Origin:Â Taiwan
- Nib:Â Stainless steel
- Nib sizes:Â EF, F, M, B, 1.1 stub
- Filling system:Â Piston filler (1.9mL)
- Body:Â Transparent polycarbonate
- Trim:Â Iris plated trim over stainless steel
- Cap:Â Twist
- Grip:Â approx. 10mm
- Diametre:Â approx. 13mm
- Length:Â approx. 142mm (capped)
- Weight: approx. 29g (capped)
- Comparable size:Â Pilot Custom 74, Lamy Studio
The Diamond 580 Iris captures what we love about fountain pens. A practical tool, that looks cool. It keeps the experience of writing visually alive.
