Dominant Industry Alchemist C04 Moonstone – 25ml Colour-Changing Calligraphy Ink (Dip Pen & Brush)

Step outside with a page written in Moonstone and watch it change before your eyes. No trick, no filter — just UV-reactive pigment doing exactly what its name promises, shifting the ink's colour the moment sunlight hits it and quietly reverting the second it doesn't.

Dominant Industry Alchemist C04 Moonstone is a 25ml calligraphy ink from the Alchemist Series, part of the Color-Changing sub-line alongside Alexandrite, Philosopher's Stone, and Seraphinite. Made in small batches in Paju, South Korea, it takes its name and its behaviour from the gemstone itself — a stone whose colour seems to shift depending on how the light falls across it, echoing the changing phases of the moon.

Available at Shosai (shosai.ca) in Gatineau / Ottawa — with in-store pickup (J9J 0K6) and Canada-wide shipping.

The Colour Change

Indoors

Out of direct sunlight, Moonstone sits as a pale, creamy orange to peach tone — soft and unassuming on the page, with a subtle pearl shimmer that catches light without demanding attention.

In Sunlight

Step into direct sun or UV light and the transformation happens within seconds: the pale orange shifts into a muted, grayish blue — some describe it as leaning indigo, others as a soft teal-grey — depending on the intensity and angle of the light. The shimmer becomes more visible against the darker tone once the shift occurs. Bring the writing back indoors or out of direct light, and the colour gradually fades back to its original orange, ready to shift again the next time it sees the sun.

How Long It Takes

The change is fast — typically visible within seconds to under a minute in direct sunlight — and fully reversible every time, for as many cycles as you care to test it.

Before You Fill Your Pen

Moonstone is a dip pen and brush ink only. This is not a suggestion — using it in a fountain pen risks permanent clogging, due to the high concentration of photochromic pigment and shimmer particles the colour-change effect depends on. Stick to dip nibs, glass pens, and brushes, and you'll get the full effect without the risk.

Practical Notes

Preparing to Write

Shake the bottle well before each use to keep the pigment and shimmer particles evenly distributed — a stir stick can help prevent air bubbles if you're working the ink for an extended session. Dry time runs longer than a standard fountain pen ink, so allow extra time before handling written pages.

Recommended Paper & Tools

Moonstone works well on smooth calligraphy paper, dip-pen-friendly surfaces, and anywhere you want the colour shift to read clearly. Pair it with dip pens, glass pens, or brushes for the fullest expression of both the base colour and the shift.

Recommended Uses

• Secret letters and hidden messages — text that reads one way indoors and reveals itself differently in the sun
• Calligraphy and creative lettering — a genuine conversation piece for any handwritten piece meant to be seen in daylight
• Outdoor art journaling — the shift is most dramatic and immediate in direct sun, making outdoor sessions especially rewarding

About the Alchemist Series

The Alchemist Series is Dominant Industry's collection of specialty calligraphy inks built around transformation, myth, and materials that don't behave the way ordinary ink does. Moonstone belongs to the Color-Changing sub-line, alongside Alexandrite, Philosopher's Stone, and Seraphinite — inks designed to shift under UV exposure and return to their original state indoors, while the Pearl sub-line (Apatura Metis, Unicorn) relies on glitter and the Standard sub-line (Blue Rose, Pink Robin) on colour alone.

About Dominant Industry

Dominant Industry is a South Korean ink studio based in Paju, working in small batches and building each release around a specific visual idea. Their inks are made through an additive process using reflective and transparent pigments, aiming for what the brand calls "bottled light" — colour with genuine presence and, in the case of the Alchemist Color-Changing line, colour that responds to the world around it.

Product Specifications

Available at Shosai — Ottawa–Gatineau

Shosai (shosai.ca) is a fine stationery boutique serving the Ottawa–Gatineau National Capital Region. We carry a curated selection of premium fountain pen inks, papers, and writing instruments from the world's most respected stationery brands.

• 📍 In-store pickup: Gatineau, QC — J9J 0K6
• 🛵 Local delivery: Available in the Ottawa–Gatineau area
• 🚚 Canada-wide shipping
• 🇨🇦 Bilingual service — English and French

Whether you are new to fountain pens or a seasoned collector, Shosai is your local destination for inks that go beyond the ordinary.