Russ,
One thing about lever backs is MOST brands have a tiny spring of base
metal in them that melts down readily when soldered. there is one
brand called “Secura” that has no spring so it’s safe to solder a
ring or bail, whatever, on to the earring. So an earring,
particularly a leverback isn’t a great example due to the spring
inside the assembly.
…However sheet or wire is the better example to discuss…Spring
gold anneals like normal gold: To anneal, heat the metal to 1200 F
for 10 to 15 minutes in an oven or kiln, or bring to a cherry red
color for 30 seconds with a torch. Follow this with a quench. This
insures that the alloy will respond to age hardening and develop its
characteristic durability. 14 kt yellow or 18 kt yellow spring gold
is specially formulated so that when it is heat treated, it will
harden the alloy in with the fine gold. All soldering should be done
before heat treating with the 18kt (or the 14 kt for that matter
though there is a bit more latitude with the 14 kt). With yellow
spring golds, you can use a lighter gauge and still maintain the
strength and durability of your piece. The gold will retain its
temper which works well for ring bridges, earrings, earring posts,
clasps, and bar type items like a money clip, tie bar, etc. or
basically for any lightweight jewellery. Then To age- harden, heat
the metal for one hour in a furnace at 700 F (370 C). Air cool the
metal before pickling . This process* is reversible and any heat
treated item can be re-softened or re-heat treated after
annealing*…so you can turn your alloy into non-spring gold- or
re-age harden after annealing but doing so more than once, maybe
twice with a 14 kt alloy (yellow) you will probably not be able to
regain the spring temper, and/or the spring temper will be lost as
the zinc content in many alloys (i say this as some karat gold
alloys are zinc free) becomes affected during pickling and the alloy
may not roll out well, particularly if you aren’t adding at least 50%
new fine gold or clean alloy to the melt or you may get a phenomenon
like stress corrosion happening (sometimes called “fire cracking”).It
is a common phenomenon with white golds, (nickel based alloys) and
low karat golds ( if one considers 6 kt actually gold, then 6-10 kt
gold alloys- those low karat alloys are more common in Europe than
the US). I hope this explains it to you: you can buy or make spring
gold and the process is reversible back to ordinary tempers, but not
spring gold once you have re-annealed it and age-hardened the stock.
White golds are a different story with many variables such as the
alloy- is it nickel based, or palladium included, and the karat makes
a difference as well. spring gold in high karats are virtually
impossible to achieve, that’s why any karat other than 14, and from
some 18 karat ordinarily available from manufacturers are a ‘special
order’ item, if they can be fabricated at all. and in thinking about
the different manufacturers i have dealt with spring gold is only
available in 14 kt as sheet and wire and only in yellow, maybe red or
’peach’ from one maker, and in 18 kt then, only as wire from a single
maker… the more fine gold an alloy contains the less 'alloy" is in
it to age-harden. rer
