GMK CYL Prussian Blue

GMK CYL Prussian Blue Base Kit (unlabeled)
GMK CYL Prussian Blue Logo
GMK CYL Prussian Blue on Amano
GMK CYL Prussian Blue on Ripple TKL
GMK CYL Prussian Blue on an ISO-DE TKL

GMK CYL Prussian Blue is a custom keycap set to be manufactured in the Cherry profile by GMK Electronic Design GmbH.

Prussian Blue’s design celebrates the languages of Poland and Germany, as the former Kingdom of Prussia intersected both of these modern nations. Likewise, I want to celebrate my own family heritage; my grandmother and generations before lived in the Prussian town of Bublitz, which is now the Polish town of Bobolice.

These MX-compatible keycaps will be made from ABS plastic and doubleshot legends (with UV front-print where needed). GMK Prussian Blue uses a simple color scheme with a GMK stock white (CP) for its legends and a custom color for the base: RAL 230 20 20 (Preußischblau).

GMK CYL Prussian Blue will be available to preorder as part of a Group Buy from March 21 to April 20, 2025.

Vendors

Base Kit

GMK CYL Prussian Blue Base Kit (final, labeled)

The base kit will support both standard US ANSI and the modern Polish Programmers’ keyboard localizations. This kit provides support for 60%, 65%, 75%, TKL, Alice, and 1800 layouts as well as “4-key” physical support for many 40% layouts.

Base kit render by Beesley.

Child Kits

GMK CYL Prussian Blue Compatibility Kit (final)
GMK CYL Prussian Blue German Mods Kit (final)
GMK CYL Prussian Blue NorDEUK Kit (final)
  • Compatibility Kit
    • This provides additional size and legend compatibility beyond what is included in the base kit, including a 6u spacebar, 1.5u System keys, Numpad equals, and more 40s support.
    • Windowed keys for Number Lock, Caps Lock, and Scroll Lock LED indicators are also included.
  • German Mods
    • When combined with the base and NorDEUK kits, this kit provides the keys necessary to recreate several full German-language keyboard layouts (like ANSI-DE and HHKB-DE), similar to the German Base Kit previously offered in 2022.
  • NorDEUK Kit
    • This kit provides language layout support for UK, German, Swedish, Norwegian, and Danish layouts.

All child kit renders by Beesley.

Board Renders

The following renders were created by two different artists (Beesley and Manzel). Each artist used different lighting models for portraying the color standard, and some boards are rendered in multiple lighting scenarios to further simulate some of the visual range of that standard. Renders may contain inaccuracies and should not be considered the final authority on the appearance of the caps.

Amano

Polycarbonate Amano Alice-style split keyboard by Amano Studio. US layout. Requires only the base kit. Renders by Beesley.

GMK CYL Prussian Blue on Amano
GMK CYL Prussian Blue on Amano
GMK CYL Prussian Blue on an Amano keyboard

W1-AT

W1-AT keyboard by GEONWORKS. German ISO layout. Note that the macro keys on the lefthand side were excised from the German Mods kit, so those will unfortunately not be available; users would likely use F1-F10 instead. Renders by Beesley, 2024-25.

GMK CYL Prussian Blue on W1AT
GMK CYL Prussian Blue on a W1AT keyboard
GMK CYL Prussian Blue on W1AT

Mech27 TKL

The Mech27 TKL, depicted with a custom color and a German ISO layout. Renders created by Manzel for the original 2022 Group Buy.

GMK CYL Prussian Blue on an ISO-DE TKL
GMK CYL Prussian Blue on an ISO-DE TKL
GMK CYL Prussian Blue on an ISO-DE TKL

MB-44

MB-44 keyboard by MelonBred. Polish programmer’s layout. Requires only the base kit. Renders by Beesley, 2024-25.

GMK CYL Prussian Blue on an MB44 Keyboard
GMK CYL Prussian Blue on an MB44 Keyboard

Bear

Bear 65% split Alice-like keyboard by Jacky. Renders created by Manzel for the 2022 Group Buy.

GMK CYL Prussian Blue on Bear by Jacky
GMK CYL Prussian Blue on Bear by Jacky
GMK CYL Prussian Blue on Bear by Jacky
GMK CYL Prussian Blue on Bear by Jacky

Ripple TKL

Ripple TKL keyboard by CannonKeys. Polish programmer’s layout. Requires only the base kit. Renders by Beesley, 2024-25.

GMK CYL Prussian Blue on Ripple TKL
GMK CYL Prussian Blue on Ripple TKL
GMK CYL Prussian Blue on Ripple TKL
GMK CYL Prussian Blue on Ripple TKL
GMK CYL Prussian Blue on Ripple TKL

GMK Color Samples

These are photographs of the GMK-produced samples for RAL 230 20 20. They were photographed from a few different angles and in different lighting contexts using an iPhone camera, with no color correction outside of what the iPhone does automatically.

Comparisons

As stated above, GMK Prussian Blue will include one custom color (RAL 230 20 20). Its legends will be GMK stock white CP. Below is a diagram that compares the estimated sRGB hex colors of several prior GMK and Signature Plastics keysets with those of GMK Prussian Blue.

GMK Prussian Blue Color Standard Comparison

Further Color Standard Photographs

The particular color standard for this set, RAL 230 20 20, is a bit tricky to photograph, and its appearance can shift significantly based on lighting and the angle of view. Below are several photos of the standard.

The first photo shows the RAL swatch using standardized metered lighting and color correction for sRGB representation (thanks Beesley!). The rest are just ordinary iPhone photos of a large sheet of this RAL in and around my house. I have applied no filtering or color correction to these other than what the iOS camera might perform by default. I hope these photos can provide a more realistic notion of how this color can look in different settings.

Background: Prussian Blue

Prussian Blue is a chemical compound originally discovered in Berlin at the turn of the 18th century. It has been used in a variety of settings from art (Japanese woodblock painting) to architecture (a traditional blueprint dye) to medicine (a treatment for heavy metal poisoning).

Prussian Blue was also used for nearly two centuries to dye the military uniforms of the Kingdom of Prussia. The RAL standard and this keyset draw from this darker variant, and GMK CYL Prussian Blue’s kitting takes further inspiration from the history of the Kingdom of Prussia itself.

The Kingdom of Prussia

The Kingdom of Prussia was established circa 1701 and existed until approximately 1918. Its borders changed frequently, with many of its parts split into separate enclaves and exclaves. Though it was ruled by a German-speaking monarchy, its reality was far more diverse, including regions of Germans, Poles, Lithuanians, and Silesians. For most of its existence, however, the majority of Prussian territory lay within the current borders of Germany and Poland.

GMK Prussian Blue Deskmat Draft
Prussian borders circa 1820 superimposed over modern central Europe.

An Unfortunate Note About Hate Speech

Unfortunately, the chemical Prussian Blue has become affiliated in some modern contexts with a failed pseudoscientific attempt to discount evidence of the Holocaust. Likewise, some obscure white supremacist music group also uses the name. Normally, I wouldn’t mention such things (as it risks giving them more attention than they deserve), but comments about these topics came up several times during the 2022 run.

As a believer in human rights, I want to say clearly and completely that I oppose Holocaust denialism, antisemitism, white supremacy, and hate speech, and this set is in no way meant to endorse any of that hateful rubbish. This set is an exploration and celebration of ancestry, history, language, and color; it is not an endorsement of nationalism or racism.

Acknowledgements

  • Thanks to my amazing wife, who has remained supportive even as my home office fills with more keyboards, keycaps, color standards, and cardboard boxes.
  • Thanks to my adorable daughter, who brings me such joy.
  • Huge thanks to Beesley for the beautiful updated renders, as well as his patience while we figured out the subtle differences between the official RAL standards!
  • Thanks to Afresh & konstantin for their immense help with getting the ogoneks right.
  • Thanks to Manzel for his renders in 2022.
  • Thanks to hunghingdailo, who gifted me with a brilliant logo.