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Extradimensional Umber

PN100718

Regular price: $29
Regular price: ~~$29~~
Sale price: $29

Free shipping offer* $75+

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Orders Ship From Pennsylvania

An ultra-saturated quasi-sheening sepia, Extradimensional Umber bends the color wheel. With a robust sepia base and a hint of green sheen at the right angle, stretching to sandy caramel on a speedier stroke, this hue will surely be one of the most mind-bending in your collection.

WARNING: Photographing the character in this ink is difficult. I've done my best to capture the extradimensional nuance, but you're bound to find something new as you play with stronger and weaker saturations on different papers in various lighting atmospheres. Our ink swatch is produced with a cotton swab on Tomoe River paper.

Since this is an extremely saturated ink, some pens may operate on the dry side and extra effort may be required in cleaning. Extradimensional Umber is part of the Keystone Formula fountain pen ink line, built with water soluble dye-colorants. The 100mL volume will provide approximately 125 standard converter refills assuming a 0.8mL draw.

Technician Log

Colorant Class: Water-soluble dye.
Saturation Profile: Rich colorant density; exhibits "dryer" flow dynamics. This property can be mitigated with our Dilution Solution elixir.
Vehicle Architecture: High-purity aqueous diluent with additives for rheology, hygroscopy, lubrication, surface tension, and biostatic stability.
Application Note: Optimal performance achieved with wet or broad+ nib geometry.
Maintenance Protocol: Increased pen cleaning frequency recommended.
Substrate Interaction: Secondary chromatic "sheen" properties manifest in saturation on coated "fountain-pen-friendly" papers.
Molecular Stability: Contains photosensitive colorant. Requires environmental hygiene and UV-mitigation to maintain color persistence.
Crystalline Integrity: Surface-level crystalline "sheen" deposits are non-lightfast and prone to photochemical degradation (universal among sheening inks).

A Chemistry Of Color

How It's Made

Our fountain pen ink formulas are developed in-house using fine colorant and a meticulously tuned vehicle. Every bottle reflects our commitment to performance, value, and creative exploration.

Formula Guide

We've compartmentalized our fountain pen ink recipes into four principal categories characterized by differentiating elements of the colorant component in the formula. A colorant is a dye or pigment that exhibits color. An ink vehicle is a series of chemicals used to transport colorant from storage reservoir to substrate (paper in our case).

Keystone Formula inks are engineered using water-soluble dyes to produce a broad spectrum of colors with a variety of unique and desirable writing properties. Fitting the bill for a traditional fountain pen ink, this series by far the most popular.

Delicate Formula inks are constructed with dyes selected for both performance and washability. Colors in this series will clean easily from most fabrics and surfaces with soap and water.

Everlasting Formula inks are compounded with pigmented colorants to produce highly water-resistant and archival properties on most papers.

Twinkle Formula inks are formulated using hybrid dye and pigment combinations to create a unique twinkling luster.

Sample Recipe

Atomink Element

Prepared In Pennsylvania

From The Maker

Skip the middleman and get the best experience by purchasing directly from a maker. As a tiny Pennsylvania based manufacturer, we're here to stand behind your purchase with expert guidance and support.
Packed With Care

Glass bottles are cartoned and individually wrapped in repurposable cellulose wadding for added cushioning and protection in transit. Meticulous care is applied to every package to ensure product arrives safely and ready to enjoy.
Ships From PA

All of our packages ship from Pennsylvania within 1-2 business days on average, unless otherwise prominently noted in the product description.
Free Freight Offer

Free shipping offer* active for orders $75+ within the continental USA.
A flat $9 shipping rate is available for all other orders continental U.S. with calculated rates for Alaska & Hawaii.
International shipping is not available.

Quality In The Details

Our fountain pen ink formulas are developed in-house using fine colorant and a meticulously tuned vehicle. Every bottle reflects our commitment to performance, value, and creative exploration.