I've been restructuring my house a few months ago and I discovered the world of encaustic cement tiles. A technique of coloured, pressed cement from the beginning of the 20th century with the most amazing patterns.
While it's a modern technique, many of the patterns in reality are based on much older Islamic tile and mosaic designs.
While planning various options for the house I made and printed some wallpapers to see if it worked. Using pictures from various online catalogues.
Inevitably, at a certain point I tried how it looked with some miniatures having Arrakis meets Marrakech in mind.
Some of the test prints were blue tiles, and had a somewhat icy aspect. Then I had the idea that there must be tiles that looked like snowflakes that would be great for Frostgrave. And indeed they exist!
I also found some antique Moroccan ceramic design. So here a few of the designs a did, for you to download and print out. I print two pictures on one page, using Windows, for the right size. I recommend heavier, semi-gloss paper for the best effect.
Edit: more tile designs: