Crushed Stone, Millstones, and Mortar can be made in a Quarry. You will need certain resources that you can find on the locations or make yourself.

For the production of Crushed Stone, you'll need Stone, and Wood. They can be obtained from various types of stones and trees in the locations.

To make Millstones, you'll need Stones and Ropes. Ropes can be made in a Tent.

To make Mortar, you'll need Crushed Stone and Clay. Clay can be found for the first time on the Kata'el Lake.