I had 50lbs of these handed to me and they said they were electrical components. Has anyone ran across these. I have been refining gold for a couple of years, and cement out the silver from the cooks. Just wandering what I'm dealing with.
The points in the second picture (pic to the right) of your original post are most definitely the tungsten/silver type points
You can tell they are the W/Ag type points due to the waffle pattern on the bottom/back side of the point (the side that brazes the point to the buss bar
That waffle pattern will be true with ALL W/Ag point so that is how you identify them from other type points
W/Ag points run between 30 - 40 % silver
To recover the silver from W/Ag points you have to "leach" the silver "out" of the "sintered" W/Ag matrix
To do that you have to literally BOIL the points for HOURS in nitric (plus distilled water)
With larger points (like in the pic) this can take as much as 2 days (48 hours) of BOILING the points in nitric to get all the silver leached out of the sintered W/Ag matrix
Although some points have Cd alloyed IN the actual point not all points have Cd alloyed IN the points & the Cd IN the points is usually VERY low in percent
Most of the Cd associated/found in processing points comes from the solder/braze used to braze the points to the bus bar as they use a much high percent of Cd in making the alloy for the solder/braze as the Cd lowers the melt point of the braze so that the braze does not melt the actual point when brazing the point to the bus bar
In other words - the vast majority of the Cd associated with the processing points comes from the braze still stuck to the points after de-soldering them from the bus bars
For what it is worth
Kurt
