From raw materials to finished products, a Longquan sword has to go through five core processes, including hammering, planing, polishing, inlaying, and quenching. From the early iron sword, it evolved into a steel sword and a folded pattern steel sword.

Hammering: Put the iron block in the furnace and burn it to a high temperature, and repeatedly forge it through the carburizing process to form the best prototype of the sword.

Planing: Use a steel knife to file the sword to make the thickness of the sword moderate, and there is a certain slope between the sword spine and the blade. The sword spine must be in the middle of the sword body and form a straight line.

Polishing: Put the filed sword on the stone and polish it. First do rough grinding, then fine grinding.

Inlay: After polishing, use a steel needle to engrave the pattern, sword name, and store number on the sword body, inlay it with red copper, and after copper plating, it will be golden after polishing, creating a color contrast and a sense of spiritual light and treasure.

Quenching: Use traditional quenching methods to make the sword body both hard and soft. This is a high-precision process that is beyond the reach of ordinary craftsmen.

In ancient China, steel was made by repeatedly folding, forging and deforming steel.

Its characteristics are repeated heating and forging. Repeated forging can remove inclusions in the steel and reduce the size of residual inclusions, so that its composition tends to be uniform, the structure tends to be dense and the grains are refined, improving the performance of the steel.

Ancient craftsmen heated and forged "fine iron" more than a hundred times, weighing and lightening each time they forged, until the weight did not decrease, which was called hundred-fold steelmaking.