Choosing fountain pen inks means deciding whether a specific writing color matters more than bottle size and listed price. In this head-to-head, Diamine Oxblood points toward red Ox Blood writing, while Private Reserve Infinity centers on black ink. The useful shortcut is simple: choose the ink that matches your page color first, then use the $3.87 price spread and bottle details to settle the tie.
Quick verdict
Choose Diamine for Ox Blood/red writing and the larger 80 ml bottle. Choose Private Reserve Infinity for black ink, extended cap-off time, and the lower listed price. The main decision is color and format rather than a claim that one ink is universally better.
Price and attribute comparison
| Ink | Listed price | Bottle detail | Notable use cue |
|---|---|---|---|
| Fountain Pen Ink Bottle Oxblood Red 80 ml Writing Calligraphy Ink | USD 20.82 | 80 ml glass bottle | Ox Blood/red writing and calligraphy |
| Private Reserve Infinity Fountain pen Ink Bottle. 30ml, Brand New | USD 16.95 | 30 ml bottle | Black ink and extended cap-off time |
Where each ink wins
- Diamine Oxblood wins for a color-led choice: Ox Blood/red is the clear reason to select it, and the bottle is the larger of the two listed sizes.
- Private Reserve Infinity wins for black-ink routines: Its black color, lower listed price, and extended cap-off time make its use case distinct.
- Price tie-breaker: The absolute listed-price spread is $3.87, so the color choice should lead unless bottle size or cap-off behavior is especially important.
Product notes
Fountain Pen Ink Bottle Oxblood Red 80 ml Writing Calligraphy Ink
Diamine Oxblood is the straightforward pick when the writing color is the deciding factor. It is identified as Ox Blood and red, and the 80 ml glass bottle gives it the larger listed volume in this matchup. That makes it a clear fit for someone specifically seeking red fountain pen ink rather than black. The trade-off is the higher listed price and a color choice that will not suit a black-ink brief. The ink is also presented for writing and calligraphy, so the product's stated use covers more than ordinary note-taking. If your priority is an Ox Blood shade in a larger bottled format, the Diamine name and title make that choice easy to identify.
Private Reserve Infinity Fountain Pen Ink Bottle
Private Reserve Infinity is the cleaner match for a black-ink routine. Its listed color is Black, and its description highlights resistance to fading and feathering along with extended cap-off time. Those characteristics give it a clear use case for writers who prefer black on the page and may leave a pen uncapped for a period. The limitation is the smaller 30 ml bottle compared with Diamine's larger bottle, so bottle volume points in the other direction. Its lower listed price also matters if the color choice is already settled. Choose Private Reserve when black ink and cap-off time are central; choose Diamine when Ox Blood or a larger bottle matters more.
Final choice by use case
- For red writing or calligraphy: Choose Fountain Pen Ink Bottle Oxblood Red 80 ml Writing Calligraphy Ink for its Ox Blood/red color and larger bottled format.
- For black everyday writing: Choose Private Reserve Infinity Fountain Pen Ink Bottle for its black color and extended cap-off time.
- For the lower listed price: Choose Private Reserve Infinity; the listed prices differ by $3.87.
- For a larger bottle: Choose Diamine Oxblood, whose listed 80 ml format is larger than the 30 ml Private Reserve bottle.
The final call is therefore uncomplicated: color leads, while bottle size, cap-off time, and the price spread settle close decisions.
