“but has few other practical uses”
That is a rather short sighted viewpoint. You need to see a bigger picture rather than a nerdy technical one.
Gold, diamonds, and other earthly materials of rare supply are storages of labor as you cannot make these things out of thin air. They must be had through labor intensive efforts. Labor is a storage of wealth as labor is life. Life is time. Labor, time and life cannot be made out of thin air.
Hence, gold is a storage of wealth. Not because it has some nerdy technical usage but because it has the practical value of storing labor, time and life. You can’t cheat it by creating it like a dollar bill or a like a digital database can have zeros added at will. You can hold it, unlike digital dollars. You can trade it, exchange it, and anyone who has more of it earned it as it took great pains to get it out of the ground.
Excellent points.