The Stonemason is part of your colony’s crafting line. The Stonemason can craft items and blocks made entirely out of cobblestone, stone, andesite, diorite, granite, quartz, nether bricks, purpur, prismarine, sandstones, and/or ores (no ingots). The Stonemason will only make items when they have been taught the recipes, receive a request for an item, and have the needed materials.
Note: The Stonemason can only learn a set number of recipes based on their hut level. So: