Index · Edition · de-koelner-dom-2024

DEDeutsche Post AG2024-06-06MainstreamHistoric Buildings in Germany

Cologne Cathedral — Crypto Stamp 2

AI-interpreted with DALL-E

The second crypto stamp from Deutsche Post features Cologne Cathedral as an AI-generated motif (DALL-E). Released on 6 June 2024 with a mintage of 100,000 booklets – a 60 percent reduction from the Brandenburg Gate edition. This edition introduced the four-color tier system: Pink (2,000 pieces, 2%), Blau (10,000 pieces, 10%), Lila (25,000 pieces, 25%), and Gelb (63,000 pieces, 63%). The NFTs were minted on the Polygon blockchain. A parallel wet-glued variant without NFT component was issued with 982,000 copies.

Variants

Variant	Color	Mintage	Rarity
Pink	#FF69B4	2,000	1
Blue	#1F4FA8	10,000	2
Lila	#8B4789	25,000	3
Yellow	#F5C518	63,000	4

About the Kölner Dom Crypto Stamp 2024

The Kölner Dom crypto stamp issued on 6 June 2024 is the second edition of the Historische Bauwerke in Deutschland series. Three adjustments distinguish it from the predecessor Brandenburg Gate edition: halved mintage (100,000 vs 250,000), introduction of a four-color lottery system, and first official naming of AI software (DALL-E by OpenAI).

The Four-Color Tier System

With Cologne Cathedral, Deutsche Post introduced rarity tiers into the German crypto stamp program for the first time — a mechanic already established in the international crypto stamp world (see Austrian Post's joint family with five-color system). The German variant has four color tiers:

Color	Share	Pieces	NFT stamp
Pink	2 %	2,000	Pink
Blue	10 %	10,000	Blue
Purple	25 %	25,000	Purple
Yellow	63 %	63,000	Yellow

The self-adhesive stamp itself is identical in motif across all four color variants. Only the surrounding booklet design (booklet cover) and NFT coloring differ. Color choice at order time is not possible — delivery is in a neutral, sealed envelope on a random principle. Opening the envelope voids the legal right of withdrawal.

Deutsche Post also introduced the 4-pack — a set with guaranteed all four color variants for combined sale. This allowed collectors to ensure completeness of their collection without lottery risk.

DALL-E Officially Named

While the Brandenburg Gate edition spoke only generically of an Artificial Intelligence, the Federal Ministry of Finance for Cologne Cathedral explicitly names DALL-E (OpenAI) as image generator:

The motif of the stamp shows how an Artificial Intelligence specialized in image and drawing creation interprets the world-famous building. (Federal Ministry of Finance, June 2024)

Motif: Cologne Cathedral: DALL-E. Numerals Nominal: © ConstantinVonavi/shutterstock.com. Value: 100 cents. (program description)

This transparency followed the public discussion about AI authenticity after the Brandenburg Gate edition. Final stamp layout design was again handled by Bonn-based graphic designer Jan-Niklas Kröger — although Deutsche Post publicly clarified that designers do have the final word, but for Cologne Cathedral the AI output was taken over unchanged.

The Image Error Controversy

This unchanged adoption sparked philatelic controversy. Collectors and Cologne residents discovered distorted architectural details in the AI rendering: an element interpreted as scaffolding looked irritating and disrupted the overall impression, tower proportions did not match the real cathedral. In the Cologne Stadtanzeiger and collector forums, this was criticized as careless.

Deutsche Post confirmed to heise.de the decision: the flawed AI output had been taken over unchanged because that was the AI's interpretation. This contradicted earlier post statements that humans have the final word in stamp design — a discrepancy discussed in the philatelic trade press.

This established a program characteristic: the German crypto stamp series preserves AI output even when this produces visual errors. This position distinguishes Deutsche Post from issuers like Austrian Post, whose CSA series undergoes extensive curation.

The Presentation at DOMFORUM

The official presentation took place on 6 June 2024 at DOMFORUM Cologne. Present were Dr. Alexander Plum (Vice President Product Management Private Customers Mail, DHL Group) and Dompropst Msgr. Guido Assmann (head clergy at Cologne Cathedral).

The Dompropst commented: When Cologne Cathedral adorns a stamp, that is good — and pointed to the countless historical depictions of the cathedral on stamps of earlier programs. The AI interpretation was thus a modern addition to a long visual tradition. The image error discussion he commented with the remark that the flawed depiction was actually surprisingly human.

Sales Performance: Conversion Data

Cologne Cathedral conversion data showed similar patterns to the Brandenburg Gate edition:

Metric	Brandenburger Tor	Kölner Dom
Crypto mintage	250,000	100,000
Wet-glued mintage	800,000	982,000
Crypto retail price	EUR 9.90	EUR 9.90
Face value	EUR 1.60	EUR 1.00
Activated NFTs (Aug 2024)	~2,800	~1,000
Conversion rate	1.1 %	1.0 %
Crypto sold out?	no	no
Wet-glued sold out?	yes (mid-Nov 2023)	yes (shortly after release)

Despite mintage halving and the new lottery system, the conversion rate remained virtually identical at 1.0%. The four-color system enriched collector mechanics, but the price differential (EUR 9.90 for a EUR 1.00 stamp) remained a barrier for most buyers.

Program Adjustments

The Cologne Cathedral edition introduced several program adjustments:

Mintage halving: reduction from 250,000 to 100,000 pieces
Four-color tier system: differentiation mechanic following international models
DALL-E naming: transparency after AI discussion of Brandenburg Gate edition
Image error retention: AI output preserved without human correction
Wet-glued sell-out: continued strong demand for traditional format
4-pack introduction: guaranteed complete set option

The Cologne Cathedral edition shows that Deutsche Post addressed the weak conversion numbers through structural changes — mintage reduction and lottery mechanics — but without significant impact on NFT adoption rates. Follow-up editions continued the trend of mintage reduction while the conversion rate remained low.

Frequently Asked Questions

What was structurally new about Cologne Cathedral compared to the Brandenburg Gate?

The Cologne Cathedral edition brought four substantial changes: The mintage was halved to 100,000 pieces after weak sales of the predecessor edition. A four-color tier system was introduced with Pink, Blue, Purple and Yellow at rarity tiers of 2, 10, 25 and 63 percent — as a differentiation mechanic to stimulate collector demand. For the first time, the Federal Ministry of Finance named DALL-E as the specific AI software instead of just referring to artificial intelligence. Additionally, a 4-pack was available allowing collectors to purchase a set with guaranteed all four color variants rather than facing lottery risk.

What was the controversy about the AI rendering of the Cathedral?

The DALL-E generated motif contained visible image errors: distorted architectural details, an element interpreted as "scaffolding" that looked irritating, proportions that did not match. Cologne residents and classical collectors criticized this as careless. Deutsche Post confirmed to heise.de that the flawed cathedral was deliberately taken over unchanged the way the AI had generated it. This contradicted earlier post statements that humans have the final word in stamp design. This discussion sparked a broader debate about AI authenticity vs. human curation in state-issued philately.

What is the conversion rate for the Cologne Cathedral edition?

As of 24 August 2024 — about eleven weeks after sales launch — roughly 1,000 NFTs of the Cologne Cathedral edition had been activated according to Polygonscan. With a mintage of 100,000 booklets, this corresponds to a conversion rate of about 1.0 % — comparable to the Brandenburg Gate (1.1 %). In contrast, the motif-identical wet-glued stamp without NFT (mintage 982,000 pieces) was sold out shortly after release. This confirms the pattern: buyers want the stamp motif, not the NFT component.