From their web site: For fifty years Harpswell House has been crafting unique and distinctive products from natural materials. Today we continue this tradition by producing some of the highest quality recognition products and gifts in the world from domestic slate. The story of slate began 300 million years ago. Finely divided particles of silt and clay were deposited in prehistoric lake beds. These particles were compressed under tremendous pressures and temperatures during upheavals of the earth's surface, forming the material we now call slate. Different colors of slate are determined by the color of the mud that was present at the time it was formed. We use red and green slate from Vermont and grey/black slate from Eastern Pennsylvania to craft our products. Some of the features of natural slate are the beautiful veining that can be seen in it, and the naturally occurring deposits in the stone, shown as darker, lighter, or different color spots embedded in the stone. These marks are caused when there is a mineral like iron that gets compressed when the slate is formed and then shows up as dark spots on the smooth honed surface, as bumps in an imprint, or as irregularities in the ridges of the cleft. Because of these markings, you know each piece is unique, with its own character. These markings are a true testament to the naturalness of the stone. Today, slate offers surprisingly versatile and contemporary applications for artisans, designers and architects. Slate's soft, uniform composition and grain make it a workable stone. It is an extremely stable material with many uses. Estate sale find and very cool looking. It appears from the web site, they no longer make this type of box except as a special order. Will ship USPS with tracking to winning buyer