X marks the silver spot: 2018 silver proof 10p coin

If you have ever dreamed of finding a buried chest overflowing with gold and silver, The Royal Mint’s 2018 Silver Proof 10p Letter X is the closest thing to real-life pirate treasure you can hold in your hand today. Part of the highly popular A to Z Great British Coin Hunt, this specific letter embodies pure adventure with its "X Marks the Spot" theme. While the general public was busy sorting through ordinary pocket change for the base-metal versions, savvy precious metal stackers quietly targeted this limited-edition masterpiece. Struck in 6.50 grams of .925 sterling silver, its flawless proof finish makes the design pop, featuring a classic, crinkled pirate treasure map and a majestic tall ship cutting through the high seas.

There is a brilliant psychological trick to this coin that makes it a fantastic addition to any silver stash. In the precious metal world, collectors love a challenge, and thousands of people are constantly competing to assemble the ultimate 26-piece silver alphabet. Because the letter X naturally taps into our collective childhood obsession with hidden loot, rogue captains, and high-seas folklore, it has become one of the most fiercely sought-after letters in the entire series. Even better for British stackers, because this is official UK currency, it is completely exempt from Capital Gains Tax (CGT)—meaning if you ever decide to sell your pirate booty down the road, your profits stay entirely yours.

If you are ready to add this piece of numismatic plunder to your collection, you will want to keep a sharp eye on how it was packaged. The absolute prize for collectors is the ultra-limited version that came sealed inside an official Royal Mint acrylic presentation block, though finding one intact on secondary markets like eBay can feel like hunting for actual buried treasure.