Looking for pure copper or Cu/Au bananas

Should I?  All kidding aside, I offered that as encouragement to "other folk" to not avoid solder.  Your reason for the choice  wasn't stated.  I'm a rank beginner DIY unlike others here.  Among the posters here, there are a handful I always read and learn from and you're among them.  Thanks for the Sir reference though.   Wait, doesn't that make me sound old?  

Eric, not only will you hear many improvements between your old and the new speaker cables ( I do question the higher frequencies of the newer cable ), you will enjoy, and question, the break in period, as there WILL be a break in period. I remember re-terminating my Deltron bananas for the Furez. Deltron = single hold down screw. Furez = crimp, no solder. After a very long break in period ( 3 weeks of 24/7 play ), the Furez started to compliment my system, as the performances were enhanced. After 2 months, they had completely broken in. Good luck.....Enjoy ! MrD.

I went with pangeas xtreme spades and bananas at amp from audio advisor.

I like using pure unplated copper spades.  The Pangea Audio Xtreme Spades are made from Tellurium Copper (C14500?) so conductivity should be about 90-93% IACS (International Annealed Copper Standard), which is as good as it gets for a copper alloy.  I doubt you would ever hear a difference between those and pure copper.

The conductivity differential becomes more pronounced with materials like C36000 Brass, C54400 Phosphor Bronze, C17500 Beryllium Copper, which have low conductivities in the range of about 19% to 40% IACS.  My old Classe' Twenty Five amplifier had brass binding posts.  Most banana plugs are made from a copper alloy, which is why the KLE bananas that are made from silver plated pure copper are so well respected.