Sunset Stone

Immediately upon the founding of Daring Heights, Viscount Willum Daffles made one of the first orders of business establishing a quarry in the mountains about a day's travel to the west to start bringing in stone to the town. No one had really checked it thoroughly, but stone was stone, right?
Mostly right, it turned out. The quarry, under the watchful management of Zara Axebreaker, soon was set up and churning out a good rate of stone, with carts trundling back and forth along little more than an animal track between the mountains and Daring. However, the stone's quality was odd. It wasn't soft or in anyway not stonelike, but Zara's initial letters back to the masons and builders of Daring Heights detailed the odd layering and patterns to it.
Stone of course is often found in layers, or even with numerous layers within a small space, but the cuts coming out of the Sunset Spine were something else. It was hard to see unless you got close to it, but what from a distance appeared a somewhat hazy light grey was in fact a hundred, a thousand even, tiny layers of different colours stacked on top of each other. It was as if the thinnest slices imaginable of different stones were stacked on top of each other and compressed. In fact, that's largely what Zara posited.
"Imagine a world," she wrote in her 3rd letter, "where the climate changes drastically enough every few years that the very stone that is being accumulated is different. I think that might be where we are making our home."
Nevertheless, it still made a good building material - if it was good enough to hold up a mountain, it was good enough for Daring. Much of the town is now comprised of this light grey stone, and only the inquisitive even notice that, the closer you look, the more layers you can find in every brick and stone around - markings of a history too intricate and varied to calculate.