There are many spring golds. Some old formulas heat treat to a
reasonable amount of spring without special additives. Our #75N/D
alloy is one of the oldest, most understood alloys- basically half
copper half silver. Use that to make 14 or 18kt as a simple one. If
you need more spring than that you need something with an additive.
Some use magnesium, some nickel, we have both. But it takes some
experience to get the heat and the timing just right with any of
them. We plan to make a video out of Gary Dawsons heat treating
seminar at Kraftwerks this weekend. We will have copies of the
basics of the website fairly soon I think. Feel free to contact me
next week when I get back to my desk at HQ.