Fountain pen inks are one of the great pleasures of the hobby — and one of the things beginners underestimate most. When you move from cartridges to bottled ink, a universe of colour opens up: hundreds of shades, from the workaday to the extraordinary, each with its own character, sheen, and personality. This guide explains everything you need to start exploring it sensibly.
Cartridges vs bottled ink
You have two ways to get ink into a fountain pen: a cartridge (a pre-filled sealed tube that clicks into the pen) or a bottle of ink that you fill from using a converter or built-in filling mechanism. Both work; they suit different situations.
Cartridges are simpler, cleaner, and more portable. You keep a few in your bag; when the pen runs dry, you swap one in. No bottles, no spillage risk, no technique required. The trade-off: cartridges are available in far fewer colours than bottled inks, are more expensive per millilitre in the long run, and many brands use proprietary formats that can't be swapped between brands.
Bottled inks give you access to everything — the full colour ranges of Pilot Iroshizuku, Diamine, Sailor Shikiori, J. Herbin, and dozens of other brands. Filling from a bottle takes a minute and becomes second nature quickly. Bottles are more economical: a 50ml bottle typically costs less than a box of cartridges while delivering several times the ink. The only real disadvantages are that you need a bottle at hand to refill, and there's a minor spillage risk during filling that cartridges don't have.
The recommended path: start with cartridges to learn how the pen works, then buy a converter and a bottle of a good all-purpose ink as soon as you feel comfortable. From there, the world opens up.
Dye-based vs pigment-based inks
Most fountain pen inks use dye-based colour — dyes dissolved in water. This covers the vast majority of coloured inks, from basic black through vivid Japanese colours to shimmer and sheen inks. Dye-based inks are easy to clean, available in hundreds of shades, and generally well-behaved.
Pigment-based inks use finely ground solid particles suspended in liquid. They tend to be more waterproof and fade-resistant than dye inks. The trade-off: pigment inks can clog pens if left to dry in the feed, requiring cleaning every one to two weeks rather than every month. Platinum Carbon Black is the most widely used pigment ink for fountain pens — it produces an archival, document-grade black.
For most beginners, dye-based inks are the right starting point.
Wet and dry inks
Inks vary in how freely they flow — described as wet (flowing generously) or dry (flowing conservatively).
Wet inks produce richer, more saturated lines, show shading and sheen more dramatically, and tend to feel smoother. They take longer to dry, are more likely to bleedthrough on absorbent papers, and can cause issues in pens that already run wet.
Dry inks flow more conservatively, dry faster, behave better on ordinary papers, and are more forgiving for left-handed writers. Pilot Iroshizuku inks are known for being wet and well-behaved. Lamy inks and Pelikan 4001 are known for running drier — useful for everyday writing on ordinary paper.
Shading, sheen, and shimmer
Three properties of fountain pen inks that don't exist in ballpoint or gel pens.
Shading is when an ink produces different tones within a single letter — darker where ink accumulates and lighter where the nib moves fastest. It gives writing a handmade, calligraphic quality. Most visible with wet-flowing pens, medium to broad nibs, and smooth, low-absorbency paper.
Sheen is a second colour visible in the ink when held at an angle to light — a blue ink that sheens red, a green that sheens copper. Sheen is only visible where ink pools thickest on the page surface, and requires slow-drying paper (Tomoe River is ideal), a generous flow, and the right light. Not all inks sheen; those that do are often sought after specifically for this. Pilot Iroshizuku Yama-budo, Diamine Ancient Copper, and Sailor Jentle Yamadori are among the most celebrated.
Shimmer is fine metallic particles in the ink, creating a glittery effect on the page. Shake or roll the bottle before filling, store filled pens horizontally rather than nib-down, and clean more frequently than you would with standard inks.
Water resistance
Most dye-based inks have low water resistance — a splash of water will smear or dissolve the writing. For most journaling and note-taking, this doesn't matter. For writing that must survive moisture — an address, notes in the rain, important documents — you need a water-resistant dye ink, iron gall, or pigment ink.
The most reliable waterproof options: Platinum Carbon Black (pigment), and modern iron gall inks like Diamine Registrar's Blue-Black and the Platinum Classic series. Among dye-based inks, those labelled "water resistant" will remain more legible when wet, but still smear.
Which inks to start with
Best first ink: Pilot Iroshizuku, in any colour. Smooth, well-behaved in virtually every pen, easy to clean, and available in an extraordinary range. The wide, low bottle makes filling straightforward even when nearly empty. Our personal favourites include Tsuki-yo (teal-blue with red sheen), Kon-peki (vivid azure), and Yama-budo (deep magenta with gold sheen).
Best for the widest colour range: Diamine. The largest colour range of any single brand, at accessible prices. Generally not water-resistant, but beautifully behaved and easy to clean.
Best for students and note-takers: Lamy or Pelikan 4001. Dry-running inks that work well on ordinary paper, dry quickly, and behave predictably in any pen.
Best for permanence: Platinum Carbon Black (pigment) or Platinum Classic (iron gall).
How to store ink
Keep bottles sealed tightly and stored away from direct sunlight and heat — a cool, dark cupboard is ideal. Stored correctly, ink will last for many years. If white fluffy growth appears in a bottle, that is mould — discard the ink. Dark sediment at the bottom of some inks (particularly iron gall and heavily saturated colours) is normal; gently rolling the bottle redistributes it.
Never put used ink back into a bottle. Never leave an open bottle out — it will evaporate and thicken.
What cannot be used in a fountain pen
Only inks specifically labelled for fountain pen use should go into a fountain pen. The following will damage pens:
- Calligraphy ink (contains shellac or gum arabic that hardens in the feed)
- India ink or drawing ink (contains binding agents that clog permanently)
- Inkjet printer ink
- Alcohol-based inks (common in marker refills)
If you accidentally use an incompatible ink, flush the pen immediately with water and continue flushing until the water runs clear.
Browse the full fountain pen ink range at The Journal Shop, including Pilot Iroshizuku, Diamine, Sailor Shikiori, and more.
Where to start: browse our fountain pen inks and fountain pens at The Journal Shop.
