Daniel Smith Walnut Ink is Fugitive. Lightfast Test Results, Art, Review.
Daniel Smith's walnut ink is fugitive despite being labeled lightfast (test results below). This is a thin, watery brown liquid ink sold in a small 2oz plastic jar. It can be applied with a brush like watercolor or used with a dip pen. It is not waterproof, dry under layers will readily dissolve when new wet layers are placed on top. It can be scrubbed and lifted when used on watercolor paper, similarly to watercolor paints. You can find Daniel Smith's walnut ink for purchase at Blick, Amazon or Jackson's.
The ink is so thin that not all fountain or dip pen nibs will work well. Because it's so fluid it can quickly dump/run off the tip of your pen. Fine line nibs can result in a pale scratchy writing/drawing experience. Gum arabic could be added to thicken the ink for better dip performance, or just use a paint brush to apply. I was able to draw using a gold coated nib (such as Speedball's gold plated 513-EF Pen Nib). Glass pens, or other nibs with larger reservoir/points may hold more ink, which results in long lasting dispensing where you can write full or multiple words at a time.
There is confusing information about this product online regarding its ingredients (most sites have misleading wording that implies this is not genuine walnut, but instead a similar looking type of ink that "resembles" walnut). The label on the jar simply says "acid-free, natural walnut colored drawing ink". Daniel Smith's website clarifies that this product is made from walnut husks. Considering this is a natural organic substance, which is highly acidic when sourced and changes color by reacting with the air, it doesn't seem like an ideal substance for fine art where archival and lightfast materials are preferred.
-art before and after-
Cons: This ink goes down as a warm brown, but has a substantial desaturation into a dull cooler brown as it dries. It continues to darken over time, with notable hue shifts visible within a week. It can be extremely difficult to anticipate the final color and value while you are painting. This means you could think something looks perfect as you paint it, just to find it looks terrible once dry. It also does not hold gradient blends on wet, the thin ink flows into any damp paper areas. This can add challenges when painting skies/clouds or anywhere you want a soft light to dark color transition.
Aside from wet to dry shift and lightfastness problems, the packaging itself leaves a lot to be desired. I've gotten such nice glass pen ink bottles for products that cost over $10 like this ink, but this is thin plastic. Liquid in a large mouth jar is prone to condensation on the inner lid. Over time I've repeatedly gotten crusty dry brown powder all over my desk from the dried ink around the edges of the screw top. Despite opening the lid carefully I sometimes splash my hand with drops coming from the condensation on the lid top. It's an accident waiting to happen, the only positive that can be said about it is the opening is large enough to dip a brush or pen into it.
Regarding safety for fountain pens: Probably not a good idea, as genuine walnut has been known to cause corrosion on metal nibs over time. However, this was due to high acidity and this product claims to be acid-free/PH neutral. I would not use this in an expensive pen, but there are very cheap pens/nib replacements which may allow this to be less of a concern. It's likely that Daniel Smith has either adjusted the PH with an additive, used a non-walnut brown dye or pigment, or otherwise treated walnut hulls in a special way to reduce acidity. I have not PH tested the ink to verify the acid free claims, however I can tell you that this ink is absolutely NOT lightfast.
This website description on the Daniel Smith website claims that this walnut ink is lightfast and this information has been passed along to all major retailers. They do not give a rating. IF any testing was ever done it's possible a heavy handed masstone sample could pass for 1-2 months before drastic fading becomes apparent. However, when diluted with water this ink quickly loses any UV resistance. By the time you reach 50/50 ink to water the fading becomes apparent within 1-2 months. The following is how the ink looks in full strength masstone (top) and water diluted (bottom) after 6 months. For comparison - at this time of indoor, south facing, vertical window (limited sun exposure, not roof/sky facing) there is typically little to NO fading in "lightfast" LFI-LFII rated watercolors. To see this much fading in a short duration is on par with ASTM ratings of LFIII-LFIV:
Daniel Smith is well known for their professional watercolor paints and have also recently started making gouache. This brand is overall very high quality, BUT there are over a dozen colors throughout their product lines which are mislabeled as lightfast. Their watercolor catalog includes nearly 300 colors though, so you'll likely still find a similar color that will work well for your needs AND be lightfast. There's a list on the watercolor review page about which pigments are known to fade.
IF you are planning to use walnut ink with a brush, basically as a liquid watercolor, I recommend using a brown watercolor instead. Many PBr7 based Burnt Umber or Sepia colors will closely resemble walnut ink, without the potential acidity or lightfast problems.
IF you want a liquid, pen-ready, drawing ink that is lightfast, waterproof, safe for fountain pens and fine art painting, then I recommend ROHRER & KLINGNER SKETCH INK instead. You can find R&K SketchINK here = Jackson's online. The colors Carmen (Yellow-orange), Vroni (magenta) and Marlene (Phthalo Blue) make a great primary mixing trio so you can DIY any color ink for your technical or fountain pen drawing. It instantly dries waterproof so you can watercolor on top of it without smearing the lines.
Daniel Smith walnut ink is for sale on Amazon, Blick, Jacksons and other online art supply shops:
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My favorite American art supply chain store is Blick. They have a massive catalog and competitive prices, with quick shipping options here in the USA.
One of my favorite places to shop for a world-wide selection watercolor paint and brushes is Jackson's. They have affordable shipping to the USA and a lovely selection of items not easily found in American stores.
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