Crystals Formed In Silver / Palladium Solution

[Purplesquish]

Ran into something new today… I am processing about 100 grams of relay contact. 80% of them are gold/palladium contacts from T-Bar relays, according to the data sheet. The remaining 20% are mixed gold plated contact that I assume are mostly silver.

I incinerated the contacts before any chemical processing to remove any surface contaminants. After that I just did a straight dilute nitric leech which seemed to progress normally. The only addition aside from the nitric was a small amount of distilled water used to spray down the beaker. After the reaction was complete, and nothing but the gold fools remained undissolved, I pulled the beaker off of the heat and left it to cool. When I returned a large amount of clear/pale crystals had formed at the bottom of my beaker. I am just curious if anyone has run into this before, and if there is any risk of incurring losses because of these crystals.

 

[FrugalRefiner]

I'm guessing silver nitrate crystals. Silver nitrate, like most chemicals, is more soluble in hot solutions than in cool solutions. Try adding some more distilled water and heat if needed to see if they dissolve.

Dave

 

[jadedalex]

Purple, Frugals answer isn't a guess. Silver will crystallize in cold dilute nitric. If your solution turns greenish, you also have copper...

 

[nickvc]

To further confirm Dave’s reply remember that water will evaporate much more easily than acids so if you use heat most of the fumes coming off are water with small amounts of acid so as Dave advised add water and heat and the crystals will disappear.