Results of cutting stones at a jewlers:
90+% == stone cabochon
>5% == stone craft
>5% == large stone gem
Only really useful if you can't start the glass industry, or have ceramic industry.
If you have glass industry with magma, make green glass gems, and encrust stone crafts. You can produce individual crafts worth over 500 urist.
If you have magma ceramic industry, make ceramic crafts, and encrust with cabochons. Again, you can get reasonably expensive trade goods, but not as good as stone base with green glass gem.
Best is either obsidian base or ceramic base, with glass gems. Those are both infinite item genrators without scarcity.
However, if you have an overabundance of stone, the benefit of stone cabochons is that they make use of bins, so you can put a whole lot more of them in a whole lot smaller space. You can encrust crap, like wooden bolts you intend to use for hunting, or training weapons, to train up jewelers, and make the ammo your dwarves use look more bling.
One of the benefits of cabochons is that, like gems, the same item can be encrusted many times with different kinds of cabochon. That large fireclay pot can be encrusted with gabbro, microcline, orthoclase, basalt, and puddingstone, all at the same time, and because each pass is multiplicitive, even though the multipliers are low, you can end up with a radically valuable item.
(Eg, 10* stone pot, x 2* stone, x5* stone, x2* stone, x5* stone ends up at 1000*, with only 24* of input materials. If those are all just "hanging rings", "spikes," etc, then you come in with an x50* gemstone, to put the image on, you now have a 50,000* stone pot. Empty, not counting the skill level bonuses applied.)
You can easily add over 2 million net worth just by encrusting all your barrels with cabochons.