This is in response to Lucia, who has 10# of industrial contact points and wants to know how to process them.
I assume that you mean the type points that are pictured in the large photo on this thread. It's hard to spot the points in the photo, although I see one or two. Mainly, the copper bussing that the points are silver soldered to is the most visible.
http://goldrefiningforum.com/phpBB3/viewtopic.php?t=202
This post does not concern the small points commonly found on relays. They are a totally different deal.
The large points are found on large electrical panels, switches, starter motors, etc. There are two basic types: (1) those made of solid coin (90%) silver. (2) Those made of tungsten powder held together with silver. I've seen coin silver points as big as 2", or more, in diameter and 1/8" thick.
The tungsten points are thinner and much harder than the coin silver ones. They are also worth much less although I don't remember their value. The figures 25% and 40% silver stick out in my mind. Harold probably knows the exact values. You can tell the difference by trying to cut a thin slice off one edge with a knife. The coin silver ones cut fairly easy whereas, the tungsten points hardly cut at all. The silver points are whiter. The tungsten points often have a cross hatch pattern on one side. Both types are attached to the copper bussing by the use of silver solder. Sometimes, the copper bussing is silver plated. Don't be fooled. Underneath the plating (scrape or cut some off), you will always find pink copper or a white copper alloy containing no silver. Also, silver plated copper is basically contaminated copper.
When you sweat the points off of the copper, you must always assume that cadmium is present, usually in the silver solder. Cadmium is very toxic. When molten and very hot, it produces toxic red cobwebs that float in the air and can enter your lungs. Zinc does the same thing except the cobwebs are white. Always sweat outside and use a particle mask. Heat the copper with a cool torch, behind the point and, when the solder melts, slide the point off with something like a stainless dinner knife. The problem is, this operation takes three hands. You can put the copper in a vise. Probably, the easiest way is to first secure a coffee can so it can't move. Then, slide the point off on the edge of the can. The point will then go into the can.
I assume you want to make as much money off the points as you can. I assume your 10# are points plus solder alone and not points plus copper. To make any money, the points first must be removed from the copper.
You have two options. You can refine the points to at least 99.95% pure, cast into bars, and sell the pure for a little under spot price. Or, you can shop around for prices and sell the points, as is, without refining, for about 60 to 70% of spot.
I would sell the points as is, with no refining. Although 10# seems like a lot, it is no where near the quantity needed to economically set up the equipment required to refine to the necessary purity, at least 99.95% and better still, 99.99%. To refine, you need a fume hood, a melting furnace, a Thum silver cell, and lots of associated equipment and tools. Even for 10#, all this stuff is necessary. If you put effort and money into any other refining process, you will be disappointed. You won't get the required purity and will receive a lot less money. This is because that, to reuse the silver for most industrial purposes, it has to be at least 99.95% pure. Someone else will have to refine it to that level and, refining costs money.
If you decide to sell, sort the points into 2 piles, the coin silver points and the tungsten silver points. Sell each pile separately. If the pile is mixed, you create doubt as to it's value and the buyer will take advantage and give you less money for the total. If you can find a buyer that is knowledgeable about points, you can probably get more money. Ignorant buyers are often afraid to give you the right price because they don't know the true values.
The coin silver points are 90% silver. The silver solder runs much less. When you sweat off the points, you end up with a value of about 81% silver. This isn't always the case but, it was the average of all the points that I have processed. To figure out a fair price for selling your points, say 60% to 70%, first determine what a pound of pure silver is worth. Today's market is $14.01/tr.oz. and there are 14.58 tr.ozs. in a pound. Therefore, a pound of pure silver is worth 14.01 X 14.58 = $204.27/pound. To figure a 60% selling price, go 204.27 X .60 X .81 = $99.28/pound. For 70%, go 204.27 X .70 X .81 = $115.82/pound. If you don't often work in U.S. weights, there are 454 grams in a pound.
When I looked up the silver price, I noticed that the gold price was $684.80. This is nearing a very interesting price because, at $685.73, gold is worth exactly $10,000 per pound. A pound of pure gold is a cube about 1 7/16" or 3.64 cm., on a side. A 5 gallon bucket will hold about 800# of gold. A cubic foot, a little over 1200#.
Hope this helps.
I assume that you mean the type points that are pictured in the large photo on this thread. It's hard to spot the points in the photo, although I see one or two. Mainly, the copper bussing that the points are silver soldered to is the most visible.
http://goldrefiningforum.com/phpBB3/viewtopic.php?t=202
This post does not concern the small points commonly found on relays. They are a totally different deal.
The large points are found on large electrical panels, switches, starter motors, etc. There are two basic types: (1) those made of solid coin (90%) silver. (2) Those made of tungsten powder held together with silver. I've seen coin silver points as big as 2", or more, in diameter and 1/8" thick.
The tungsten points are thinner and much harder than the coin silver ones. They are also worth much less although I don't remember their value. The figures 25% and 40% silver stick out in my mind. Harold probably knows the exact values. You can tell the difference by trying to cut a thin slice off one edge with a knife. The coin silver ones cut fairly easy whereas, the tungsten points hardly cut at all. The silver points are whiter. The tungsten points often have a cross hatch pattern on one side. Both types are attached to the copper bussing by the use of silver solder. Sometimes, the copper bussing is silver plated. Don't be fooled. Underneath the plating (scrape or cut some off), you will always find pink copper or a white copper alloy containing no silver. Also, silver plated copper is basically contaminated copper.
When you sweat the points off of the copper, you must always assume that cadmium is present, usually in the silver solder. Cadmium is very toxic. When molten and very hot, it produces toxic red cobwebs that float in the air and can enter your lungs. Zinc does the same thing except the cobwebs are white. Always sweat outside and use a particle mask. Heat the copper with a cool torch, behind the point and, when the solder melts, slide the point off with something like a stainless dinner knife. The problem is, this operation takes three hands. You can put the copper in a vise. Probably, the easiest way is to first secure a coffee can so it can't move. Then, slide the point off on the edge of the can. The point will then go into the can.
I assume you want to make as much money off the points as you can. I assume your 10# are points plus solder alone and not points plus copper. To make any money, the points first must be removed from the copper.
You have two options. You can refine the points to at least 99.95% pure, cast into bars, and sell the pure for a little under spot price. Or, you can shop around for prices and sell the points, as is, without refining, for about 60 to 70% of spot.
I would sell the points as is, with no refining. Although 10# seems like a lot, it is no where near the quantity needed to economically set up the equipment required to refine to the necessary purity, at least 99.95% and better still, 99.99%. To refine, you need a fume hood, a melting furnace, a Thum silver cell, and lots of associated equipment and tools. Even for 10#, all this stuff is necessary. If you put effort and money into any other refining process, you will be disappointed. You won't get the required purity and will receive a lot less money. This is because that, to reuse the silver for most industrial purposes, it has to be at least 99.95% pure. Someone else will have to refine it to that level and, refining costs money.
If you decide to sell, sort the points into 2 piles, the coin silver points and the tungsten silver points. Sell each pile separately. If the pile is mixed, you create doubt as to it's value and the buyer will take advantage and give you less money for the total. If you can find a buyer that is knowledgeable about points, you can probably get more money. Ignorant buyers are often afraid to give you the right price because they don't know the true values.
The coin silver points are 90% silver. The silver solder runs much less. When you sweat off the points, you end up with a value of about 81% silver. This isn't always the case but, it was the average of all the points that I have processed. To figure out a fair price for selling your points, say 60% to 70%, first determine what a pound of pure silver is worth. Today's market is $14.01/tr.oz. and there are 14.58 tr.ozs. in a pound. Therefore, a pound of pure silver is worth 14.01 X 14.58 = $204.27/pound. To figure a 60% selling price, go 204.27 X .60 X .81 = $99.28/pound. For 70%, go 204.27 X .70 X .81 = $115.82/pound. If you don't often work in U.S. weights, there are 454 grams in a pound.
When I looked up the silver price, I noticed that the gold price was $684.80. This is nearing a very interesting price because, at $685.73, gold is worth exactly $10,000 per pound. A pound of pure gold is a cube about 1 7/16" or 3.64 cm., on a side. A 5 gallon bucket will hold about 800# of gold. A cubic foot, a little over 1200#.
Hope this helps.
