Selling by-products
Facts checked 1 Nov 2026
By now your warehouse holds a lot more than iron. The by-products of weathering, leaching, and the rest are worth SWAY, and selling them is how a real refinery pays its way.
What you'll have spare
By the end of the acid loop, you'll have roughly:
- Silica: About 1,600 tonnes, from weathering.
- Magnesia: About 1,600 tonnes, from leaching.
- Carbon Dioxide: About 2,700 tonnes, given back by leaching and iron-making.
- Zinc Oxide and Nickel Oxide: About 200 and 180 tonnes.
- Carbon Monoxide: About 250 tonnes more than the iron needed.
- Salts and Chlorine: A few tonnes, from making Calcium.
Keep what's still to come
Before you sell, check what the last course needs: the Iron, the Calcium, about 250 tonnes of Deionized Water for the cement, and your Calcite. Keep any Sulfuric Acid for your last round of leaching, too.
Sell the rest
Sell at Academy Market 2, just as in Selling at the marketplace: choose each product, then Market Sell into the buy orders waiting there. To sell several at once, select them in your warehouse and choose Market Sell Selected.
- Only Where There's a Buyer: You can only sell into buy orders that are there. If nobody wants something today, keep it and check again later.
- Your Leftover Acid: Once your last round of leaching is done, sell any Sulfuric Acid you have left at Academy Market 2. It's worth far more than any by-product, so don't leave it behind.
- Before Your Hire Ends: Anything still in the warehouse when your hire ends passes to the next student, so sell what you can in good time.