For deep etching on metal you ll definitely need an powerful YAG laser - these dont come cheap unfortunately.
The cheap (mostly chinese made 1000mW-3000mW )CO2 laser engraving machines dont work on metal at all. you will need at least a 40W co2 Laser and a special marking spray. this will burn the spray into the surface of the metal leaving a more or less grey/black surface marking of varying durability depending on the spray mostly. From what I read people had success with this method but its just a surface marking anyway and does not go deep. For that you need a more powerful fiber laser(YAG)
But You could use it to cut vinyl templates/masks... but be aware that the optics on some of them are not able to focus to a very fine dot so minimal line width and as such the level of detail is limited this is definitely a question I would ask the vendor. Jewelry stuff is usually small so detail matters.
The interface between the laser and your graphics program is also of importance , for convenience of use it should be able to accept output formats from corel, autocad or whatever else programm you use to create your pattern. Some of the cheap units only come with limited capability in that regard.

I have looked into that as an alternative but a machine that could do what I want with will be roughly in the 10.000€ range and above.... If you are content with only surface marking a much cheaper CO2 will do. So far I am sticking to etching which gives me good results and is budget friendly as well.

Prices on lasers, 3d printers, cnc milling machines and such for the casual consumer market are steadily going down and quality goes up because of demand so I guess in a few years we will see som really good stuff coming from all those kickstarter projects.. Until then I am content to stay "old school".