I make rings in two grades of titanium. Both are considered grade 5 aerospace grades. One grade, called 6Al4V has 6% aluminum and 4% vanadium added to the titanium to make it stronger. It has a minimum tensile strength of 135,000 psi. It is commonly used in jet fighter parts, as well as prosthetic implants, and sporting equipment. It finishes well and works great for rings.
The other alloy, called 8-1-1 is even stronger. It has 8% aluminum, 1% vanadium, and 1% molybdenum added to the titanium. It has a minimum tensile strength of 150,000 psi. It is commonly found in jet engine compressor blades. The color of the two grades is the same.
Either grade will do nicely for a ring. The question is, will you be pulling an airplane or a ship with your ring. :o)