Much more expensive than Titanium Arnaud. Reactive Metals Studio is the go to place . The heaviest gauge they carry is 20ga. 6"x12" for $300 +.The pendant in the photo is 24ga. OK for earrings , but a little thin for a pendant. No acid etch necessary and I find the colors to be more predictable than Titanium.
If you acid etch the titanium you can get bold colors, but without the acid etch the high end washes out. With Nb you don't have to surface prepare or acid etch and the full spectrum is vivid.