How I Turned My Niche Coin Collecting Passion Into a $50K Online Course on Teachable & Udemy
September 30, 2025How Source Code Review and Digital Evidence Analysis Can Launch a Lucrative Career as a Tech Expert Witness
September 30, 2025Writing a technical book isn’t about having all the answers—it’s about asking the *right* question. For me, it started with a ridiculous debate: “Is it a blister or a DDO?” Sounds funny, right? But that single thread—where collectors argued over a Lincoln cent with a weird bump near Lincoln’s ear—became the seed of my book, Is It a Blister or a DDO? The Technical Anatomy of Coin Varieties, now published by O’Reilly. This is how I turned a niche, heated forum debate into a technical book that major publishers actually fought over. No hype. No fluff. Just a real process that anyone can follow.
From Forum Fodder to Book Concept: The Ideation Phase
I didn’t start with a grand plan. I started with a coin, a photo, and a room full of collectors going full detective mode.
One collector posts: “Looks like a plating blister.”
Another replies: “No way—it’s a doubled die obverse.”
Then a third: “You’re both wrong. That’s just earwax.”
Humor aside, the thread exploded with over 100 posts. People shared images, cited past errors, and even questioned mint records. But beneath the banter? A real technical void: how do you *diagnose* coin anomalies with precision, not just guesswork?
That’s when it hit me.
Every anomaly—blister, DDO, die break—leaves a trace. A fingerprint. And collectors weren’t using a system. They were trusting vibes.
So I asked myself: *What if we treated coin anomalies like lab specimens—not just collectibles?*
The answer became my book’s thesis: **coin forensics**—a methodical, reproducible way to analyze coin errors using imaging, testing, and data.
Identifying the Technical Gap
I spent weeks reviewing existing resources. Here’s what I found:
- Books like The Cherrypickers’ Guide list known varieties—but don’t teach you *how* to spot new ones.
- Academic papers on metallurgy are fascinating, but they’re written for PhDs, not weekend coin hunters.
- Forums like Reddit and Facebook? Goldmines of real-world data—but zero rigor. One expert’s “blister” is another’s “DDO.”
The gap was clear: collectors needed a technical methodology, not another catalog. So I decided to write one. Not just a list of errors—but a *process* for identifying them.
My book would blend:
- Structured diagnostics: step-by-step flowcharts, not hunches.
- Imaging techniques: how to photograph coins to reveal hidden details.
- Statistical validation: using rarity data to separate common quirks from valuable anomalies.
Building a Unique Angle: The “Coin Forensics” Framework
I needed a way to organize the chaos. So I built the **Coin Forensics Framework**—a four-category system to classify any anomaly:
1. **Surface-Level Errors** – like plating blisters or debris strikes (appear after plating, not in the die)
2. **Die-Induced Errors** – like DDOs, die cracks, or chips (traced to the minting die)
3. **Post-Strike Damage** – corrosion, tool marks, or scratches (happens after the coin leaves the press)
4. **Hybrid Cases** – when two errors collide (e.g., a blister on top of a doubled die)
This wasn’t just theory. It became the book’s backbone.
Each chapter focused on one category, with:
- A clear diagnostic checklist
- Real coin examples (yes, even the “earwax” cent)
- Side-by-side image comparisons
- And a simple rule: “A blister *sinks* under pressure. A DDO *holds its shape*.”
Structuring the Book for Technical Audiences
I wasn’t writing for casual collectors. I was writing for **technical collectors**—the ones who grade coins professionally, build authentication tools, or run grading startups.
So I structured the book like a lab manual. No fluff. Just process.
Part 1: Foundations of Coin Diagnostics
- Chapter 1: Terminology—why “earwax” isn’t a technical term (and what to use instead)
- Chapter 2: Your imaging rig—how to set up a $100 macro rig that beats a $5000 microscope
- Chapter 3: Metadata—why every photo needs a timestamp, lighting angle, and scale bar
Part 2: The Diagnostic Workflow
- Chapter 4: Blister vs. DDO—the pressure test, with Arduino code to build your own sensor
- Chapter 5: Die breaks—how to use Python to detect edge shifts with image differencing
- Chapter 6: Rarity vs. value—pulling data from PCGS, NGC, and eBay to assess significance
Part 3: Advanced Techniques and Case Studies
- Chapter 7: Crowdsourcing—why 50 opinions don’t beat one peer-reviewed analysis
- Chapter 8: Writing a technical report—how to submit findings to PCGS or ANACS with confidence
Readers told me they could open to any page and *do* something. That’s the goal: a book you use, not just display.
Pitching to Publishers: O’Reilly, Manning, and Apress
Publishers don’t care about your idea. They care about three things: audience, platform, and expertise. Here’s how I showed mine.
1. Market Demand: The $200M Authentication Market
I didn’t pitch a coin book. I pitched a **tech book for a growing market**.
- PCGS’s blockchain grading—proof the industry wants automation
- Startups like CoinScan using AI to detect fakes—showing demand for better tools
- The rise of “variety hunting”—a $200M+ niche where collectors pay premiums for rare errors
My book? The missing manual for that ecosystem.
2. Author Platform: I Built an Audience Before the Book
I didn’t wait for a publisher to validate me. I built proof of interest:
- A Substack with weekly “Coin Autopsy” posts—like “The Toothpick Test: Why It’s Useless for DDOs”
- YouTube videos on macro photography for collectors—grew to 10K subscribers in a year
- Talks at numismatic conferences—on topics like “Digital Tools for Coin Analysis”
When I pitched, I said: “I already have 15,000 engaged readers. I’ll bring them to your book.”
3. The Book Proposal: A Working Blueprint
My proposal wasn’t a wish list. It was a deliverable.
- Chapter outlines with learning objectives
- Sample chapter (Chapter 4: The Pressure Test)—complete with code, images, and exercises
- Marketing plan—targeting forums, grading newsletters, and VC-backed authentication startups
- Comp titles—ANA Grading Standards (rigor), Steve Forster’s Error Coin Encyclopedia (audience)—but positioned as: “The O’Reilly Guide to Coin Forensics”
O’Reilly replied in 72 hours. Manning and Apress followed with offers. I chose O’Reilly—not just for their reach, but for their **technical audience** and **production quality**.
Navigating the Writing Process: From Manuscript to Publication
Writing a technical book takes stamina. My routine was simple:
1. First Draft: The “Barf Draft”
I wrote 2,000 words, four days a week, for six months.
Each chapter followed the same template:
[Chapter Title]
- What You’ll Learn
- The Problem (e.g., “How do you tell a blister from a DDO?”)
- The Method (e.g., “The three-point pressure test”)
- A Case Study (e.g., “The 1999-D Lincoln cent”)
- Code/Images
- “Try This” Exercise
No perfection. Just momentum.
2. Technical Review: Let the Experts Catch My Mistakes
I asked three groups to review:
- PCGS’s technical team
- Numismatic scholars
- Members of the Error-Variety Collectors Facebook group
One reviewer spotted a critical error: I’d labeled a die chip as a DDO in a case study. That saved my credibility—and taught me that peer review matters.
3. O’Reilly’s Production Pipeline
Once the manuscript was in, their team transformed it:
- Copyediting—polishing technical language
- Image processing—ensuring high-resolution, print-ready photos
- Cover design—featuring the very Lincoln cent from the original forum thread
- SEO blurb—optimized for Amazon and Google searches like “coin error guide,” “DDO identification,” and “numismatic forensics”
Building Thought Leadership Post-Publication
A book is a tool. But your platform is your power. Publishers help, but *you* own the long game.
1. Launch Strategy
- Hosted a live webinar with O’Reilly—“Coin Diagnostics 101”
- Offered a free PDF chapter for email signups (netted 3,000 subscribers)
- Partnered with Coin World for a feature: “From Forum Thread to O’Reilly Book”
2. Ongoing Engagement
- Created a GitHub repo with code samples—so readers could build their own tools
- Started a “Coin Autopsy of the Month” newsletter—featuring new anomalies and reader submissions
- Launched a Kickstarter for a companion kit—macro camera mount + Arduino pressure sensor
3. Monetization and Authority
- Now consult with grading companies at $250/hour
- Keynote at major coin shows—fees in the five figures
- Invited to advise VC-backed authentication startups
Conclusion: Your Niche Becomes Your Authority
That forum thread about a coin’s ear? It changed my life. Because I didn’t dismiss it as a joke. I asked: *What problem does this reveal?* And then I built a solution.
My journey—from “Is it a blister or a DDO?” to O’Reilly author—shows this:
- Start with a real problem, not a trendy topic.
- Design for action—readers should be able to try something after every chapter.
- Build your audience early—publishers bet on people, not just ideas.
- Turn your book into a platform—use it to launch talks, kits, consulting, and more.
Whether your “blister vs. DDO” moment is about blockchain, Kubernetes, or coin errors—your niche is your superpower. You don’t need a grand idea. You need a specific question.
Go find yours.
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