Question

[brjook]

What is the pins on CPU 's made of on a celeron after the gold plateing is removed.Wil not react with HCl and slight reaction with Nitric .Also my stannous test show a dark brown almost black color and gold should be more like purple correct .The test is on my solutions not the pins.

 

[Anonymous]

Some of them were made of kovar,definitely not worth messing with.And the stannous result sounds ok.Just make sure it stays that color and does not dissipate after a few minutes

 

[bigjohn]

Is your hcl hot? I use the hcl crockpot method for those type pins. It's slow but it works.

 

[pgm]

Some of them were made of kovar,definitely not worth messing with.And the stannous result sounds ok.Just make sure it stays that color and does not dissipate after a few minutes

if i am write i should have a dark brown colour too, this will mean i still have gold in the liquid when doing the test.

 

[Harold_V]

if i am write i should have a dark brown colour too, this will mean i still have gold in the liquid when doing the test.

Unless your stannous chloride borders on being non-functional, you shouldn't see a brown reaction, even with very little gold present. What you should see is a purple reaction, and if the concentration of gold is high enough, you may perceive it as black. In any case, if there's enough gold present to make it worth your effort, the cavity in which you conducted the stannous chloride test will have traces of a purple stain. It's one of the advantages of using a spot plate.

Harold

 

[pgm]

if i am write i should have a dark brown colour too, this will mean i still have gold in the liquid when doing the test.

Unless your stannous chloride borders on being non-functional, you shouldn't see a brown reaction, even with very little gold present. What you should see is a purple reaction, and if the concentration of gold is high enough, you may perceive it as black. In any case, if there's enough gold present to make it worth your effort, the cavity in which you conducted the stannous chloride test will have traces of a purple stain. It's one of the advantages of using a spot plate.

Harold

Thanks Harold, i have a this picture what do you think, had trouble dropping due to too much nitric but now might have put in too much smb... but still i am moving forward with it....i have a post in the help section please take a look and see it there is anything else you can add

 

[Harold_V]

In a case like this, where you have doubts, a few crystals of ferrous sulfate can prove valuable. Put a drop of solution in a spot plate cavity and add a crystal. Watch the crystal is it dissolves. If you have gold present, it will be seen as a shiny gold leaf, or even as dark brown particles. The solution should lighten in color as well.

I never used urea, and I don't suggest anyone do. However, if that be your choice, you may be well served, at this point, to cement the values using copper, and start over. As you continue to add more and more junk to the solution, I expect you'll have a corresponding increase in grief.

The very best advice I can offer is for you to follow Hoke's advice ----and duplicate her processes. They work, and work well. Do not be mislead by the thoughts that it is old technology. That "old technology" served me perfectly well for more than 20 years, and allowed me to retire when I was 54.

Harold

 

[pgm]

Thanks Harold,

AS they say OLD is GOLD...