PDA

View Full Version : What to expect from junk silver?



truerelaxation
19th June 2008, 11:02
How much silver should we expect to get in a bag of junk silver? I believe that $1000 face contains 723 troy ounces when the coins are new. I read in a post that $1000 of worn coins will contain something like 715 ounces.

Using a $125 bag of mixed Kennedy, Franklin and Liberty halves as an example:

The coins weighed 6# 13.1oz on a kitchen scale.

Converted to pounds:
6+(13.1/16) = 6.81875 #

Then Troy ounces:
6.81875*14 = 95.4625

Then silver content
0.9*95.4625 = 85.91625

Silver content when the coins were new:
723/1000 = x/125
x=90.375

The difference in silver content of new coins and this bag is:
90.375-85.91625 = 4.45875

I know that there is always wear but does 4.5 ounces seem like a lot based on the $125 face value of the bag?

The formula used by this particular dealer is
(face value)(.72)(spot price) = cost of purchase

Does that seem like a fair formula for calculating the cost?

pkrebaum
19th June 2008, 12:23
This is where you made the error:
Silver content when the coins were new:
723/1000 = x/125
x=90.375

When 723 new ounces of Silver wears, 715 are left, or 715/723 = 98.89% of the original weight.
Conversely, 723/715 converts worn ounces of Silver back to unworn, or 101.1%.

So if you have 95.4625 worn ounces, the silver weighed 95.4625 X 1.011 = 96.5126 Oz. new.
96.5126 Oz. (new)
- 95.4625 Oz. (old)
------------------------
1.0501 Oz. (lost)

Scrap Metal
19th June 2008, 14:30
Your calculations aside...I buy 90% by face value and sell it that way. I do not forsee a breakdown in this system. I am a small buyer, so I always pick really nice 1964 (or close) coins so that I do not suffer value loss from wear. If you buy a bag or partial bag on line, you get what you get.

While it is interesting to know the weight of the silver, I do not think that we will go to a system where we weigh 90% and then calculate the silver content, as the face value system is so easy to use. I just try to pick good coins so that if I have to sell, or use them for barter, the recipient will not have any reason to refuse them.

hiyosilver
19th June 2008, 18:20
90% is 90%, worn or not...if the worn coin's total weight is 12 grams, the silver content is 90% of that (10.8 grams). Don't complicate it. Just weigh your coins, subtract 10% and that's how much silver you have accurately. Just make sure you use the right formula to convert from your scale's measure to troy measure. I use a gram scale to weigh small stacks at a time. Let's say a stack weighs 246.1 grams, then the silver content would be 221.49 grams. Divide that by 31.10348 grams per troy ounce equals 7.121troy ounces.

argentos
19th June 2008, 18:53
90% is 90%, worn or not...if the worn coin's total weight is 12 grams, the silver content is 90% of that (10.8 grams). Don't complicate it. Just weigh your coins, subtract 10% and that's how much silver you have accurately. Just make sure you use the right formula to convert from your scale's measure to troy measure. I use a gram scale to weigh small stacks at a time. Let's say a stack weighs 246.1 grams, then the silver content would be 221.49 grams. Divide that by 31.10348 grams per troy ounce equals 7.121troy ounces.

Thank you for that.

My brain was hurting badly from trying to get it round pkrebaum's formulae. :confused:

pkrebaum
19th June 2008, 20:14
I was trying to show that his calculation of 4.5 ounces lost was incorrect, computing from the face value, which is what people do if they don't have a scale. But everybody has scales these days, so hiyosilver's method is far simpler since you know the weight of your coins. 100 troy ounces of 90% silver is 90 troy ounces of silver no matter how you slice it, and the 90 troy ounces is what you should be paying the coin dealer for.

BTW, to minimize measurement errors, don't ever weigh less than 10X the minimum resolution of the scale. In other words if you're using a scale that reads to +/- 1 gram, never use it to weigh less than 10 grams. 100X to 1000X the minimum resolution will give excellent results.
If you do this for a living invest in a pair of calibration weights, 10% and 90% of the scale's maximum capacity (not minimum resolution) will tell you if your scale is keeping its accuracy and linearity over time.

goldminer
19th June 2008, 20:34
Due to the size of the different 90% denominations, the wear factor is more on "average" circ. dimes then it is on quarters, more on "average" circ. quarters then halves, and more on all of these compared with "average" circ. dollar coins.

i.e. a finger tips cover/rubs the whole sides of a dime...not so with a quarter, more not so with a half, and even more no so with a silver dollar.

A bag of "average" circ. halves will always contain more Ag then a bag of "average circ. quarters or dimes.

truerelaxation
19th June 2008, 21:44
Thanks for all of the great replies.

I may have calculated the weight properly then? Pounds to troy ounces times 90%. Roughly 85 ounces. Next time I'll use grams. I may have gotten the lost metal incorrect though. It doesn't sound like lost metal is as important as taking 90% of the total weight to get the amount of silver though.

Do you guys feel that (face value)(.72)(spot price) is a good way to buy these coins?

How important is it to be able to choose the coins that go into the bag? This dealer will not let buyers select the coins and he chooses them. The bags are mixed Franklins, Kennedys and Liberties. He won't leave out the Liberties. The Liberties in the bag seem really worn. When 10 of the Liberties are stacked next to 10 Franklins and 10 Kennedys the Liberty stack is a half coin shorter than the other two stacks. The other two are pretty much the same height.

I'm also pretty sure he weighs them after they were counted. After they were counted and bagged he had his back to me from across the room and it looked like he was putting coins in and out of the bag. This went on for what seemed like 5 or 10 minutes.

There is another place in town that will charge (face value)(.715)(spot) + (.25 per dollar). Might end up costing a little more for $125 face but they let you choose what you're getting. They can compile a bag of Franklins or a bag of Kennedys for example. Not sure if its worth it?

TTAZZMAN
19th June 2008, 22:35
Then Troy ounces:
6.81875*14 = 95.4625


the correct conversion from lbs to Troy Oz ....is 14.5833

if you will change the multiplyer to the correct # the calculations will work out to a ratio # if .716

calculations as follows

723/1000 x 125 = 90.375 (as minted troy ounces in 125face)

your 125 face = 6.81875# of silver alloy

6.81875 x 14.5833 = 99.44 troy oz of silver alloy

99.44 x .90 = 89.50 troy oz of actual silver

so 89.5/125 = .716 is the actual ratio of silver in your bag

hope that clears it up

.712-.715 is a fair ratio for normal coins....i have seen 64 kennedy halves trade at .720 +

hiyosilver
20th June 2008, 00:15
BTW, here is a free program I've used for years for multiple things. Stand alone, no installation, no shareware or adware, no BS, just results.

"Convert is a free and easy to use unit conversion program that will convert the most popular units of distance, temperature, volume, time, speed, mass, power, density, pressure, energy and many others, including the ability to create custom conversions!"


http://joshmadison.com/article/convert-for-windows/

Irons
21st June 2008, 12:07
The refineries won't even buy it.These guys were recomended to me and I just shipped off a load of sterling to them I had picked up at yard sales.
They are clear on what they buy and what they pay.

http://www.midwestrefineries.com/

clr8ter
21st June 2008, 15:39
I don't know, I just sold 56 40% halves last weekend for $2.25 ea......

Irons
22nd June 2008, 07:12
I don't know, I just sold 56 40% halves last weekend for $2.25 ea......

I had to buy a bagful of ikes to get the handful of morgans that came with them, I had no problem selling off the ikes.I just took that money and bought more .999!:p

kennedyhalf
1st June 2011, 17:29
i have 3 $100 bags, two half dollar and one dime, and they weigh: dime 88.1 grams, half 87.7 gm, half 87.3 gm so half dollars not always better than dimes as the dime bag is my heaviest.