This is a very simple 10mm x 10mm cube with rounded edges.
Print it in different colors and scale it as desired. The cube can be in different colors for different resources: brown for wood, gray for iron, yellow for food, etc. Let your imagination run wild. In order not to restrict you as a user, the pages are simply blank.
If requested I can change the file for your desired size, something on its sides, completely different shapes etc.
The author hasn't provided the model origin yet.