Robert Oster Thunderstorm: Ink Review

Robert Oster Thunderstorm Fountain Pen Ink

Robert Oster Thunderstorm is part of the normal line up of fountain pen ink featuring a deep blue-grey shade reminiscent of storm clouds rolling over the horizon. This is a perfect ink for anyone looking for something unique and versatile, but still professional. Read on to find out more about this blueish grey shade!

Robert Oster Thunderstorm Ink Review

Robert Oster Thunderstorm Ink Review

Robert Oster Thunderstorm Ink Review on Dot Grid 

Ink Review 

Supplies Used:

Smear Test (Dry Time):

  • 20-30 seconds – We found this to have a relatively long dry time, so it may not be best for quick notes and fast page turning.

Drip Test (Water Resistance):

  • Low – While some of the lines were still visible, it does not have any water resistance and will run if it gets wet.


  • High – There is little to no variation from swab 2 to 3. This is a pretty dark color and may be mistaken for a black shade when using a finer nib.

Ease of Cleaning:

  • High – This ink does not have any permanence and rinses out readily with no staining.


  • Medium-High – From grey to deep blue with a touch of sheen, this ink has gorgeous layers to it.


  • Medium – Robert Oster inks are wet but tend to have a medium flow.

    Robert Oster Thunderstorm Ink Swabs and bottle

    If you're interested in similar colors, check out our Swab Shop where you can compare colors side by side.


    Overall, the performance of this ink stands out with slight shading, which provides a little depth to every stroke. A subtle sheen adds a touch of elegance and its well-behaved nature makes it an excellent choice for those who value reliability in their daily writing endeavors. This ink effortlessly offers a sleek and polished writing experience, with a dusky hue that commands attention without being overpowering.This is not one to overlook!


    Robert Oster Thunderstorm Ink Swab

    Robert Oster Thunderstorm Ink Swab

    This color is available in 50ml bottles as well as our 2ml ink samples.