Manufacturing process:

Optimizing raw materials → melting → matching ratio → primary purification → added alloying element → alloying → test → metallurgical structure control → secondary purification → functional testing → casting → furnace after testing → pallet packaging → exterior final inspection → entering warehouse

Bismuth was previously considered to be the most stable element with the largest relative atomic mass, but in 2003, it was found that bismuth had extremely weak radioactivity, and its half-life was determined to be 1.9 × 1019. This means that bismuth may not undergo visible decay before the demise of mankind.