https://techcrunch.com/2024/04/18/magnus-metal-series-b-exclusive/

Humans have cast metal parts in basically the same way for thousands of years: by pouring molten metal into a mold, often made of compacted sand and clay.

There’s a reason this ancient method is used today: sand casting is inexpensive and works well with both ferrous, or iron-based, and nonferrous metals. But there is a wasteful downside. The technique requires more metal than the finished part needs, and while scraps are usually recycled, melting excess metal over and over wastes energy. 3D printing has emerged as a pricey alternative generally reserved for prototypes and low-volume parts.