Grid Pin Arrays encasing the CPU: Gold pins vs. Silver-colored pins

as a general rule, pins that are NOT gold plated, but are used for data transfer, will be a stainless or nickel alloy. you will occasionally find a rhodium plating over a variety of base metal alloys. you will not find a pin that is designed to be corrosion resistant that is plated with an alloy. the metals used in that alloy would not be corrosion resistant and that would defeat the entire purpose. you will also find that many of the gold plated pins use nickel alloys as a base.

platinum and palladium are used as plating agents, but are not commonly found in low end electronics. one notable exception is a few of the hard drive platters. but they only have about $.30 of platinum per platter. there is debate over how much of that can be recovered and at what cost.

you can invest in a meter that has thermal testing capabilities. you could also do a resistance test. metals transfer heat at a known rate. they also resist an electrical current at different rates. either or both can be used to determine the metal in question.

if you are testing a plated surface, you must be certain that you are only contacting that plated surface and not the base metal.

these are general rules of manufacturing practices and not absolute rules.

basically, if it is not gold plated, you are not going to recover enough of any other plating to be worthwhile. one of the benefits of plating or flashing with palladium, platinum and rhodium is the ability to use a much thinner application of the metal to the base. it is more difficult and more expensive to recover and refine those 3 metals as well.

So gold = possibly good. silver = always bad

a correction on pin structure. base metal is normally copper or a copper alloy. which is then plated with nickel or stainless. nickel plated pins will often be used for the gold plated base pin.

some of the new boards are now using steel pins.

for those who are familiar with the magnetic eddy separation process, it is now obvious how gold flashed on a steel pin is being lost during the mechanical phase of ewaste processing.