Hi hello this is all true and I am gonna add to that:
- bad metal in open wound really bad. Bad metal in fully 100% inert scar tissue healed piercing sometimes still bad. Always get good metal. You CAN be allergic to good metal if you have dogshit luck, but TBH chances are it probably secretly had nickel (see: white gold, amazing mystery metal)
- this shit needs to be polished to mirror shine by hand, yo
- titanium good if good titanium (read on for more on: good titanium)
- sterling silver easy to work with for artisan, has copper as part of the alloy, which is annoyingly reactive, which makes it dogshit metal for anything you keep on your body 24/7 or overall in really high sweat/moisture area - not because it will harm you, but because your sweat has SALT and WATER and LACTIC ACID and UREA which tends to turn copper black/green. This can temporarily rub off on your skin, make the jewelry look NOT SHINY or both.
(This won't always happen immediately because sterling silver is not EXTRA SHINY, PURE silver or RHODIUM is, so they either plate it super thin or do a treatment that makes a very small amount of pure silver come to the surface. This extra shiny eventually RUBS OFF.)
- pure gold too soft for jewelry, so what you use is GOLD ALLOY. Gold easy to work with for artisan. Gold 16k and above: fine. Gold 10k? Dogshit, that is not even half gold. Yellow gold alloys usually won't have nickel, and neither will red gold. Red gold and yellow gold: fine.
But WHITE gold alloys usually DO have nickel. Why? Because nickel is CHEAP. Know what else nickel is? The main metal most people are 'sensitive' to. Or GET sensitivity to later, because prolonged exposure to nickel makes you SENSITIVE TO NICKEL. You can get specially made white gold so that does not have nickel, but that is because it has PALLADIUM instead. Which is great except it's also MORE EXPENSIVE THAN GOLD.
(I think black gold alloys have cobalt, that can be not fine to some people too I believe.)
- platinum is fine but lbr you probably can't afford platinum, neither of us can. It's okay.
- surgical steel is MYSTERY METAL, do NOT get surgical steel unless they tell you EXACTLY what is in it because 'surgical steel' means DOGSHIT. It means they could make a scalpel out of it, it does not mean it should STAY IN YOU. What you want is IMPLANT GRADE steel and they BETTER tell you exactly which alloy it is too.
- titanium can be fun colors, a rainbow of colors, the colors are fine but titanium is not black. I repeat. TITANIUM IS NOT BLACK. If titanium is black the titanium has been PVD COATED, that can flake off. And what is touching your skin/wound is, well, not titanium, so what even is the point. Again, you want an IMPLANT GRADE alloy and make sure they tell you which. Also no good for artisan, so: often boring.
- niobium is fine and can be colors and CAN be black, but just like implant grade titanium is DOGSHIT to work with. Not good for artisan unless entirely cold formed.