Combine

Some things can be combined to gain more mass, for example wood scrap, hot iron lumps and rye.

To Combine: Activate the first item then right click the second (identical) item and select Combine.

You can also combine an entire pile of identical items at once. Activate the second (or later) item in a pile and right click the pile group line (the one with a -/+ sign) and select combine. This will combine the item you have selected with the others into one item with the combined weight and the average quality of the combined items.

Note: Combining will reduce the total monetary value of the final product if they are not all of the same QL. Combining uses a linear average but the prices in game are not linear. Prices are quadratic so a quadratic sum would be more accurate than a linear average.