Adding value in stone shaping technology

This thread [Fabrication or assembling] makes me wonder about the
parameters of “adding value” in stone shaping technology.

So far what I have is cutting, grinding, chipping, molding (as in
the use of powdered alabaster and sometimes also clays in ceramics),
assembling and colouring (as in polishes and stains/paints/fillers).
Is that list exhaustive?

Should we say that “marketing” is the main parameter which subsumes
all of these physical parameters? After all, is a diamond really so
much more aesthetic than a Swarovski crystal and is it really so much
more durable in the practical sense? If an enormous amount of
craftsmanship goes into it, could it not rank beyond the rarest of
diamonds in the rarity criterion? But where does it stand in the
market place?

I am reading the Smithsonian rock and gem “Definitive Guide” (saw the
gem room at the Smithsonian too - awesome!). How much are those
malachite pillars of St. Isaac’s Cathedral worth? Or the “Amber
Room”? How much is the Smithsonian total collection worth compared
to its stones if sold individually? There are about 100 rough
diamonds scattered in the picture on pages 122-123. How much more
beauty is there in them than many other crystals at the Smithsonian
when the naked eye (mine anyway) at arm’s length cannot make a
differentiation?