How I Used My Data & Tableau Skills to Find 100 Silver Coins Last Year


My grandparents have a beach house in Island County and every 4th of July there is a big parade and community get together. One of the events is the “Penny Hunt”. The adults scatter a bunch of coins (of varying denominations) in the sand for the kids to search for. As kids, my brother and I got fed up with blindly digging in the sand so we convinced our dad to get us a cheap metal detector. I remember pulling in $40 the first summer we put it to use. Not bad for a couple of kids.


We had previously collected coins and in the process of finding the $40 found a couple of cool old coins as well (the community dates back 100+ years). We were intrigued and started looking for old coins in nearby baseball fields and parks. We let it fall by the wayside for a number of years only to pick it up again a couple years ago while looking for a shipwreck on the coast that was rumored to have lost a cargo of gold coins (disclaimer: I found no gold. Just a fork.)

Fast forward to the beginning of 2018 and my brother found a great place we could metal detect and find old coins. We did pretty well there for a few months until there wasn’t much left. I started to wonder if I might be able to find 100 silver coins over the course of the year.

For those that know me, I’m an accomplishment-driven person. I like having a goal to strive for whether that’s a half marathon time, a fundraising amount or a silver coin quota. I decided, what the heck, why not try to find 100 silver coins in 2018.

I started asking folks in my neighborhood if I could metal detect the planting strips outside their homes. Most were happy to oblige (a couple not so much haha). I met a friend who showed me a public beach where I could find some as well. By mid-summer things had gone well but I had exhausted most of my local options. Driving to other neighborhoods to meet new people and ask about metal detecting their planting strips was too time intensive. I was trying to run a business and plan a wedding.

That’s when my mind turned to my data skills. I had previously come across a few construction sites where buildings were being demolished. I had no interest in trespassing but the surrounding planting strips are city property (maintained by the adjacent property owner). The ground was all torn up from construction equipment driving across it and I’d done well in similar strips in residential areas.

I wondered if there was a way to find those kinds of sites more systematically and, as luck would have it, there was. I found a way to pull data for local demolitions and began plotting them on a map. I filtered so only properties that met my criteria showed (when permits were issued, what type of permit, etc.) and started analyzing those properties in Tableau:


I cross-referenced those sites in Google Maps to see if they had potential, and if they did, I would add them to a list to visit in person. On a Saturday morning, I might have time to visit 6 sites before I needed to be home to spend time with my wife

After a lot of weekend (and weeknight) outings, I finally found silver coin #100 on December 23rd. It’s not something I plan to do again, but it was a fun challenge.

Here’s a breakdown by type (in Tableau of course):


And here’s the breakdown of number by month:


I’m not sure if this will inspire you to find your own treasure, but I hope it demonstrated a way that you can put your data skills to work in your everyday life.


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