Contemplating the size of treasure hoards recently, it occurred to me to wonder how big a pile of cold, hard cash would be that a dragon sleeps on. Different games suggest different amounts of treasure for dragons, especially when age and type are considered. And of course some treasures should include things like cup and plate and other items that are bulkier than coins for their value.

I got out my own hoard: 200 golden US dollar coins. I put them into a small box 6 inches by 3 inches and found that–loosely packed–they fill it to an average depth of about 1.25 inches, so they take up 22.5 cubic inches of space.

When I dump them onto the floor (and kind of scoop them together), 200 coins make a pile about 6 inches by 9 inches, about 3/4 of an inch thick in the middle or about 1/2 an inch on average. That’s 27 cubic inches, which is just a little more loosely packed than the other figure. Piled into a hoard, they probably more closely resemble the boxed version.

A Treasure Chest

100,000 coins (silver or gold) would therefore loosely pack into a box of 11,250 cubic inches, or a treasure chest or strongbox 35 inches by 18 inches by 18 inches high, filled to the brim. However, according to traditional D&D rules, this would weigh 2000 pounds. (Both silver and gold pieces are 50 to the pound, so gold pieces must be smaller and/or thinner).

A Pile

Let’s say we want to look at a dragon’s hoard worth 100,000 gp. To make it a bit more impressive, we can say 90% of it is actually silver coins. So, that’s 910,000 coins, or 102,375 cubic inches, or 59.25 cubic feet.

Now, spread out on a floor, they’ll obviously thin out toward the edges, but let’s say the average depth is 6 inches. That means 59.25 cubic feet would cover 118.5 square feet. Each 5×5-foot square on a typical dungeon map is 25 square feet, so that hoard would cover roughly 5 squares–or 10, if it was only 3 inches deep. You could stretch it a bit by saying it covers a platform and includes a lot cup and plate, gilded items, and similar bulky things. So perhaps it covers 10 or 15 squares a few inches deep

Caveats

Of course, your fantasy coins may have a different shape or otherwise take up more or less space than US $1 coins. I wrote previously about historic analogs to D&D coinage.